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 A184751 #5 Mar 30 2012 17:25:56 %S A184751 0,0,0,0,1,1,2,1,1,3,2,1,3,4,4,3,1,2,6,1,1,9,8,1,3,2,2,3,1,4,12,1,1,6, %T A184751 2,1,3,16,16,9,1,2,19,1,1,12,4,19,9,2,2,3,1,8,24,1,1,18,23,1,3,19,4,3, %U A184751 1,23,19,1,1,32,16,1,3,2,2,27,1,4,12,1,19,23 %N A184751 a(n) = A184750(n)/A133151(n) unless A133151(n) = 0 in which case a(n) = 0. %C A184751 a(n) is the "level" of pentagonal numbers (A000326). %C A184751 The decomposition of pentagonal numbers into weight * level + gap is A000326(n) = A133151(n) * a(n) + A016777(n) if a(n) > 0. %C A184751 A184750(n) = A000326(n) - A016777(n) if A000326(n) - A016777(n) > A016777(n), 0 otherwise. %H A184751 Rémi Eismann, <a href="/A184751/b184751.txt">Table of n, a(n) for n = 1..1000</a> %e A184751 For n = 3 we have A133151(3) = 0, hence a(3) = 0. %e A184751 For n = 5 we have A184750(5)/A133151(5) = 19 / 19 = 1, hence a(5) = 1. %e A184751 For n = 25 we have A184750(25)/A133151(25) = 849 / 283 = 5, hence a(25) = 3. %Y A184751 Cf. A000326, A016777, A133151, A184750, A117078, A117563, A001223, A118534. %K A184751 nonn %O A184751 1,7 %A A184751 _Rémi Eismann_, Jan 21 2011