cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A352787 Numbers with as many divisors as Goldbach partitions.

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%I A352787 #12 Apr 12 2022 18:29:58
%S A352787 34,46,58,102,116,122,138,150,154,162,172,184,190,196,212,228,264,266,
%T A352787 296,304,332
%N A352787 Numbers with as many divisors as Goldbach partitions.
%C A352787 If it exists, a(22) > 7*10^5. - _Ivan N. Ianakiev_, Apr 11 2022
%C A352787 Numbers k such that A000005(k) = A061358(k). - _Michel Marcus_, Apr 12 2022
%e A352787 122 is in the sequence since it has 4 divisors {1,2,61,122} and 4 Goldbach partitions (13,109), (19,103), (43,79), (61,61).
%t A352787 Select[Range[332],DivisorSigma[0,#]==Length[Select[#-Prime[Range[PrimePi[#/2]]], PrimeQ]]&] (* _Ivan N. Ianakiev_, Apr 11 2022 *)
%o A352787 (PARI) nbgp(n) = my(s); forprime(q=2, n\2, s+=isprime(n-q)); s; \\ A061358
%o A352787 isok(k) = numdiv(k) == nbgp(k); \\ _Michel Marcus_, Apr 12 2022
%Y A352787 Cf. A000005, A061358.
%K A352787 nonn,more
%O A352787 1,1
%A A352787 _Wesley Ivan Hurt_, Apr 02 2022