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 A137936 #4 Mar 31 2012 19:52:43 %S A137936 0,5,10,15,20,1,6,11,16,21,2,7,12,17,22,3,8,13,18,23,4,9,14,19,24,5, %T A137936 10,15,20,25,6,11,16,21,26,7,12,17,22,27,8,13,18,23,28,9,14,19,24,29, %U A137936 10,15,20,25,30,11,16,21,26,31,12,17,22,27,32,13,18,23,28,33,14,19,24,29,34 %N A137936 a(n) = 5*mod(n,5) + floor(n/5). %F A137936 a(n) = 5*mod(n,5) + floor(n/5) = 5*A010874(n) + A002266(n) %F A137936 O.g.f.: -x(-5x^3+19x^4-5x^2-5x-5)/[(-1+x)^2*(x^3+x^4+x^2+x+1)] . - _R. J. Mathar_, Mar 07 2008 %e A137936 a(0) = 5*mod(0,5) + floor(0/5) = 0 %e A137936 a(3) = 5*mod(3,5) + floor(3/5) = 15 %o A137936 (Python) a = lambda n: 5*(n%5) + floor(n/5) %Y A137936 Cf. A010874, A002266. %K A137936 nonn,easy %O A137936 0,2 %A A137936 _William A. Tedeschi_, Mar 06 2008