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 A113722 #8 Mar 02 2015 16:08:50 %S A113722 1,3,5,5,5,7,7,7,7,7,9,9,9,9,9,11,11,11,11,11,13,13,13,13,13,13,13,15, %T A113722 15,15,15,15,15,15,17,17,17,17,17,17,17,19,19,19,19,19,19,19,21,21,21, %U A113722 21,21,21,21,23,23,23,23,23,23,23,23,23,25,25,25,25,25,25,25,25,25,27 %N A113722 A variant of Golomb's sequence using odd numbers: a(n) is the number of times 2*n+1 occurs, starting with a(1) = 1. %C A113722 a(n) is taken to be the smallest number >= a(n-1) which is compatible with the description. %e A113722 Start with 1 in row 1 and form a triangle where row n is generated from row n-1 by the rule given in the description. Then row 2 will have (1) 3, row 3 will have (3) 5's, row 4 will have (5) 7's, (5) 9's and (5) 11's, etc. %e A113722 The triangle begins: %e A113722 1; %e A113722 3; %e A113722 5,5,5; %e A113722 7,7,7,7,7,9,9,9,9,9,11,11,11,11,11; ... %e A113722 The number of terms in each row (also row sums with offset) is given by A113723: [1,1,3,15,135,3845,769605,3821696361,...]. %o A113722 (PARI) a=[1,3,5,5,5];for(n=3,20, for(i=1,a[n],a=concat(a,2*n+1)));a %Y A113722 Cf. A001462 (Golomb's sequence), A113723, A113724, A113676. %K A113722 nonn %O A113722 0,2 %A A113722 _Floor van Lamoen_ and _Paul D. Hanna_, Nov 08 2005