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%I #15 Jul 10 2024 20:04:46
%S 5,25,1176,1625,7385,18633,21726,30276,32923,36905,46025,50809,55449,
%T 60726,89257,102425,151657,185745,278226,289961,301017,319145,373176,
%U 394121,459513,779817,815676,827926,1053019,1055719,1170153,1399123,1657865,1663209,1667326
%N Numbers k such that phi(k) is equal to A008473(k-1).
%e phi(1176)=336, 1175=5^2*47^1, (5+2)*(47+1)=336.
%o (PARI) b(n) = my(f = factor(n)); for (k=1, #f~, f[k, 1] = f[k, 1] + f[k, 2]; f[k, 2] = 1; ); factorback(f); \\ A008473
%o isok(k) = (k>1) && (eulerphi(k) == b(k-1)); \\ _Michel Marcus_, Feb 25 2021
%Y Cf. A000010, A008473.
%Y Cf. A039779, A039781.
%K nonn
%O 1,1
%A _Olivier Gérard_
%E Title corrected and more terms from _Sean A. Irvine_, Feb 24 2021