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.

A333050 a(1) = 1; a(n+1) = Sum_{d|n, gcd(d, n/d) = 1} a(d).

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%I A333050 #5 Mar 08 2020 08:38:54
%S A333050 1,1,2,3,4,5,9,10,11,12,18,19,25,26,37,44,45,46,59,60,68,80,100,101,
%T A333050 114,115,142,143,156,157,219,220,221,242,289,303,318,319,380,408,423,
%U A333050 424,536,537,559,575,677,678,725,726,842,890,919,920,1064,1087,1107,1169,1327,1328
%N A333050 a(1) = 1; a(n+1) = Sum_{d|n, gcd(d, n/d) = 1} a(d).
%t A333050 a[1] = 1; a[n_] := a[n] = Sum[If[GCD[(n - 1)/d, d] == 1, a[d], 0], {d, Divisors[n - 1]}]; Table[a[n], {n, 1, 60}]
%Y A333050 Cf. A003238, A325446.
%K A333050 nonn
%O A333050 1,3
%A A333050 _Ilya Gutkovskiy_, Mar 06 2020