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.

A323602 Smallest b > 1 not already in the sequence such that b^(c-1) == 1 (mod c), i.e., c is a base-b Fermat pseudoprime, where c is the n-th composite number (A002808).

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%I A323602 #5 Jan 19 2019 23:21:35
%S A323602 5,7,9,8,11,13,15,4,17,19,21,20,23,25,18,27,26,29,31,33,10,35,6,37,39,
%T A323602 14,41,43,45,19,47,49,30,51,16,53,55,34,57,56,59,61,63,62,65,12,67,69,
%U A323602 22,71,73,75,74,77,76,79,81,80,83,85,38,87,28,89,91,3,93
%N A323602 Smallest b > 1 not already in the sequence such that b^(c-1) == 1 (mod c), i.e., c is a base-b Fermat pseudoprime, where c is the n-th composite number (A002808).
%C A323602 Is this a permutation of the positive integers > 1?
%o A323602 (PARI) my(v=vector(1)); forcomposite(c=1, 50, my(b=2); while(Mod(b, c)^(c-1)!=1, b++; if(Mod(b, c)^(c-1)==1, for(k=1, #v, if(b==v[k], b++)))); v=concat(v, b); print1(v[#v], ", "))
%Y A323602 Cf. A002808, A242742, A259234, A323603.
%K A323602 nonn
%O A323602 1,1
%A A323602 _Felix Fröhlich_, Jan 19 2019