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%I #12 May 19 2023 18:30:31
%S 1,2,3,13,39,55,527,776,910,942
%N Fixed points in A073673.
%C Numbers k such that A073673(k) = k.
%C a(8) > 750. - _R. J. Mathar_, Jul 14 2015
%o (PARI) v=[1];n=1;print1(1,", ");while(#v<300,s=1+n*prod(i=1,#v,v[i]);if(ispseudoprime(s)&&!vecsearch(vecsort(v),n),v=concat(v,n);if(n==#v,print1(n,", "));n=0);n++)
%Y Cf. A073673.
%K nonn,more,hard
%O 1,2
%A _Derek Orr_, Jun 22 2015
%E a(8)-a(10) from _Michael S. Branicky_, May 19 2023