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 A057768 #3 Mar 31 2012 13:50:36 %S A057768 0,0,1,1,2,1,2,2,2,2,1,2,3,1,1,1,2,2,2,2,3,3,2,4,5,2,3,4,4,2,2,2,3,2, %T A057768 1,3,4,3,4,4,4,4,5,3,3,3,2,2,2,2,4,2,3,3,3,3,3,3,3,2,4,3,2,2,4,4,4,3, %U A057768 4,3,3,4,5,4,3,3,4,3,3,1,5,4,2,3,6,4,5,5,4,4,6,4,5,3,1,2,3,4,5,4,3,5,6,3,3 %N A057768 From Goldbach problem: number of decompositions of 2n-1 into sum of a prime lucky number(from A031157) and a twin even-lucky-number(from A045955, A045956). %C A057768 Conjecture: this sequence is always positive (with n>2). %e A057768 1 and 3 are not the sum of a prime lucky number and a twin even-lucky-number, so a(1) = a(2) = 0; 5=3+2 (one way, so a(3)=1); 7=3+4 (so a(4)=1); 9=3+6=7+2 (so a(5)=2); etc. %Y A057768 Cf. A045954, A045955, A045956, A031157, A000959, A002375, A045917. %K A057768 easy,fini,nonn %O A057768 0,5 %A A057768 _Naohiro Nomoto_, Nov 01 2000