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.

A108583 Primes of the form 1 + Product_{j=1..k} b(j), where b(n) = b(n-1) + 2*A005185(n) and b(1) = 2.

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%I A108583 #18 Dec 20 2022 11:22:31
%S A108583 3,13,2593,2426113
%N A108583 Primes of the form 1 + Product_{j=1..k} b(j), where b(n) = b(n-1) + 2*A005185(n) and b(1) = 2.
%C A108583 Next term contains 886 digits. - _G. C. Greubel_, Dec 19 2022
%H A108583 G. C. Greubel, <a href="/A108583/b108583.txt">Table of n, a(n) for n = 0..4</a>
%t A108583 Hofstadter[n_]:= Hofstadter[n]= If[n<2, 1, Hofstadter[n-Hofstadter[n- 1]] +Hofstadter[n-Hofstadter[n-2]]]; (* A005185 *)
%t A108583 b[n_]:= b[n]= If[n==1, 2, b[n-1] +2*Hofstadter[n]]; (* A108585 *)
%t A108583 p[n_]:= p[n]= Product[b[j], {j,n}];
%t A108583 Select[Table[p[n] +1, {n, 500}], PrimeQ]
%Y A108583 Cf. A005185, A108585.
%K A108583 nonn,less
%O A108583 0,1
%A A108583 _Roger L. Bagula_, Jul 05 2005
%E A108583 Edited by _G. C. Greubel_, Dec 19 2022