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 A160707 #9 Jan 03 2019 03:27:02 %S A160707 1,1,3,18,192,3472,104964,5306272,450215638,64298445920 %N A160707 Convolution square root of the Robbins sequence, A005130, starting with offset 1. %C A160707 Terms are not integral beyond what's shown! - _Joerg Arndt_, Jan 02 2019 %e A160707 Self-convolution = the Robbins sequence, A005130: (1, 2, 7, 42, 429, 7436, ...). %e A160707 Example: A005130(4) = 42 = (1, 1, 3, 18) dot (18, 3, 1, 1) = (18 + 3 + 3 + 18). %e A160707 The reversed procedure given (1, 2, 7, 42, ...) for a(4) = 18 = (1/2) * (42 - 2*a(3)) = (1/2) * 36 = 18. %Y A160707 Cf. A005130, A160708. %K A160707 nonn,less %O A160707 1,3 %A A160707 _Gary W. Adamson_, May 24 2009