cp's OEIS Frontend

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.

A079422 a(n) = number of 1's in the first n^2 Spiro-Fibonacci differences.

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%I A079422 #7 Aug 13 2025 22:19:03
%S A079422 0,3,7,11,15,19,24,26,32,41,49,55,61,67,75,78,83,111,119,135,139,155,
%T A079422 160,168,182,217,229,249,259,279,293,303,312,342,399,454,493,530,566,
%U A079422 603,642,681,722,765,817,875,909,958,992,1044,1107,1160,1215,1267,1315
%N A079422 a(n) = number of 1's in the first n^2 Spiro-Fibonacci differences.
%H A079422 N. Fernandez, <a href="http://www.borve.org/primeness/spirofib.html">Graphical representations of some Spiro-Fibonacci sequences</a>
%e A079422 The Spiro-Fibonacci differences are 0,1,1,1,1,1,1,1,0,1,0,1,0,1,0,1,...(A079421). Terms are written in square boxes radiating spirally. a(n) = the sum of the first n^2 terms in A079421, i.e. the number of 1's in a spiral of height n and width n.
%Y A079422 Cf. A063826, A078510, A079421.
%K A079422 nonn
%O A079422 1,2
%A A079422 _Neil Fernandez_, Jan 07 2003
%E A079422 More terms from _Sean A. Irvine_, Aug 13 2025