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.
%I A024941 #26 Apr 22 2019 17:35:04 %S A024941 1,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,1,0,0,0,1,0,0,0,0,0,0,1,1,0,0,0, %T A024941 1,1,0,1,0,0,0,1,2,0,0,0,2,1,0,0,1,1,0,1,2,1,0,0,2,3,0,1,0,1,1,0,3,1, %U A024941 0,0,2,3,1,1,1,2,1,0,3,2,0,0,1,5,1,0,1,2,3,1,3,3,1,0,2,5,3,1,1,2,3,2,4,4,1,1,2,7,4,1,2,3 %N A024941 Number of partitions of n into distinct primes of the form 4k + 1. %C A024941 a(0) = 1 corresponds to the empty partition {}. %H A024941 Alois P. Heinz, <a href="/A024941/b024941.txt">Table of n, a(n) for n = 0..10000</a> %e A024941 a(41) = 1 since it can be expressed as a sum of primes of the form 4k + 1 in only one way: a trivial partition containing just itself. %e A024941 a(42) = 2 since 42 = 5 + 37 = 13 + 29. %e A024941 Although 43 = 2 * 13 + 17 = 6 * 5 + 13, none of those consist of distinct primes only. Hence a(43) = 0. %t A024941 searchMax = 120; primes4kp1 = Select[4Range[Floor[searchMax/4]] + 1, PrimeQ]; Table[Length[Select[IntegerPartitions[n, All, primes4kp1], DuplicateFreeQ]], {n, 0, searchMax}] (* _Alonso del Arte_, Apr 17 2019 *) %o A024941 (PARI) { my(V=select(x->x%4==1,primes(40))); my(x='x+O('x^V[#V])); Vec(prod(k=1,#V,1+x^V[k])) } \\ _Joerg Arndt_, Apr 19 2019 %Y A024941 Cf. A024942 (4k - 1). %K A024941 nonn %O A024941 0,43 %A A024941 _Clark Kimberling_ %E A024941 Definition clarified by _Felix Fröhlich_, Apr 17 2019 %E A024941 a(0) = 1 prepended by _Joerg Arndt_, Apr 19 2019