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 A173508 #11 Nov 17 2019 01:44:15 %S A173508 1,1,1,2,2,3,4,6,8,11,15,20,28,38,52,71,97,132,181,247,337,461,629, %T A173508 860,1174,1604,2191,2993,4089,5585,7630,10422,14237,19448,26567,36291, %U A173508 49574,67720,92507,126367,172620,235804,322114 %N A173508 a(n) = ceiling(A173497(n)/2). %p A173508 A173497 := proc(n) option remember; if n <= 1 then op(n+1,[2,1]) ; else procname(n-1)+procname(n-2)-floor(procname(n-2)/2) ; end if; end proc: %p A173508 A173508 := proc(n) ceil(A173497(n)/2) ; end proc: %p A173508 seq(A173508(n),n=0..60) ; %Y A173508 Cf. A000032, A064323, A173497. %K A173508 nonn %O A173508 0,4 %A A173508 _Roger L. Bagula_, Nov 23 2010 %E A173508 Definition corrected, Mma code related to another sequence removed, sequence extended