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%I #9 Jun 13 2021 03:24:12
%S 1,20,196,368,650,672,780,836,1888,2352,3192,11096,17816,20496,30240,
%T 51060,84660,130304,979992,1848964,2291936,3767100,4526272,8353792,
%U 15126992,15287976,23569920,33468416,45532800,74899952,381236216,623799776,712023296,1845991216
%N Nonprime numbers k such that A054008(k) = A054024(k).
%C If p is an odd prime then A054008(p) = A054024(p) = 2. Therefore, this sequence is restricted to nonprime numbers.
%e 20 is a term since it is a nonprime number and A054008(20) = A054024(20) = 2.
%t Select[Range[10^6], !PrimeQ[#] && Mod[#, DivisorSigma[0, #]] == Mod[DivisorSigma[1, #], #] &]
%Y Cf. A000005, A000203, A054008, A054024.
%Y Subsequences: A047728, A245782.
%K nonn
%O 1,2
%A _Amiram Eldar_, Apr 08 2021