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**1000 sequences decomposed into weight × level + jump**on my website. Before continuing, I would like to have an independent verification of my data. There is a complete dump of my database on the home page (.sql.zip, ~105 Mo, central table “sequences” and 1 table per sequence).

#math #numbers #sequences #OEIS #primenumbers #mathematics

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**New decompositions:**

A145749: Numbers n such that sigma(n)+phi(n)=sigma(n+1)+phi(n+1).

A152470: Largest of three consecutive primes whose sum is a prime.

A156849: Numbers n such that n^2 == 2 mod (23^2).

A157468: Primes of the form sqrt(p-1)-1, where p is a prime.

Now

**1000 sequences decomposed**into weight × level + jump on https://decompwlj.com (https + responsive)

#math #maths #mathematics #numbers #sequences #primes #OEIS #primenumbers

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**New decompositions:**

A141165: Primes of the form 9*x^2+7*x*y-5*y^2.

A157483: Numbers n such that n-1 and n+1 are divisible by exactly 3 primes, counted with multiplicity.

A158714: Primes p such that p1 = ceil(p/2) + p is prime and p2 = floor(p1/2) + p1 is prime.

A158913: Primes p such that there is a composite c with sigma(p) = sigma(c).

Now

**996 sequences decomposed**into weight × level + jump on https://decompwlj.com (https + responsive)

#math #maths #mathematics #numbers #sequences #primes #OEIS #primenumbers

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**New decompositions:**

A127341: Primes that can be written as the sum of 13 consecutive primes.

A136333: Numbers containing only digits coprime to 10 in their decimal representation.

A137812: Left- or right-truncatable primes.

A141161: Primes of the form 4*x^2+6*x*y-7*y^2.

Now

**992 sequences decomposed**into weight × level + jump on https://decompwlj.com (https + responsive)

#math #maths #mathematics #numbers #sequences #primes #OEIS #primenumbers

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**New decompositions:**

A118954: Numbers that cannot be written as 2^k + prime.

A119449: Primes with even digit sum.

A121943: Numbers k such that the central binomial coefficient C(2k,k) is divisible by k^2.

A125022: Even numbers with a unique partition as the sum of 2 squares x^2+y^2, divided by 2.

Now

**988 sequences decomposed**into weight × level + jump on https://decompwlj.com (https + responsive)

#math #maths #mathematics #numbers #sequences #primes #OEIS #primenumbers

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**New decompositions:**

A107181: Primes of the form 8x^2 + 9y^2.

A111046: Difference between squares of twin prime pairs.

A117048: Prime numbers that are expressible as the sum of two positive triangular numbers.

A118134: Primes p such that 4p is the sum of two consecutive primes.

Now

**984 sequences decomposed**into weight × level + jump on https://decompwlj.com (https + responsive)

#math #maths #mathematics #numbers #sequences #primes #OEIS #primenumbers

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**New decompositions:**

A101095: Fourth difference of fifth powers (A000584).

A103664: Primes p such that the number of divisors of p-1 is less than the number of divisors of p+1.

A105441: Numbers with at least two odd prime factors (not necessarily distinct).

A106881: Primes of the form x^2+xy+9y^2.

Now

**980 sequences decomposed**into weight × level + jump on https://decompwlj.com (https + responsive)

#math #maths #mathematics #numbers #sequences #primes #OEIS #primenumbers

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**New decompositions:**

A097103: Numbers n that are the hypotenuse of exactly 22 distinct integer sided right triangles, i.e. n^2 can be written as a sum of two squares in 22 ways.

A097933: Primes such that p divides 3^((p-1)/2) - 1.

A099204: A variation on Flavius's sieve (A000960): Start with the natural numbers; at the k-th sieving step, remove every p-th term of the sequence remaining after the (k-1)-st sieving step, where p is the k-th prime; iterate.

A100493: a(n) = n + n-th semiprime.

Now

**976 sequences decomposed**into weight × level + jump on https://decompwlj.com (https + responsive)

#math #maths #mathematics #numbers #sequences #primes #OEIS #primenumbers

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**New decompositions:**

A090693: Positive numbers n such that n^2 - 2n + 2 is a prime.

A091300: Nonprimes of form 6k+1.

A092022: Numbers n such that 16n + 3 is prime.

A092192: Semiprimes that are the sum of two successive semiprimes.

Now

**972 sequences decomposed**into weight × level + jump on https://decompwlj.com (https + responsive)

#math #maths #mathematics #numbers #sequences #primes #OEIS #primenumbers

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**New decompositions:**

A087054: Primes of the form pq + qr + rp where p, q and r are distinct primes.

A087248: Squarefree abundant numbers.

A089194: Primes p such that p-1 and p+1 are cube- or higher power-free.

A089589: Iban numbers (the letter i is banned from the English name of the number).

Now

**968 sequences decomposed**into weight × level + jump on https://decompwlj.com (https + responsive)

#math #maths #mathematics #numbers #sequences #primes #OEIS #primenumbers #pythagorean #squarefree

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