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%I #10 Mar 19 2018 06:43:22
%S 30823866178561,796928461056001,1802582780370364661761,
%T 2827987212986831882236723201,
%U 68688966922031309945174465761834751373920047004215278394826366933532673
%N Primes of the form 1 + 5-multiperfect numbers.
%C A subsequence of A093034. If p is a term of this sequence then for each positive integer k, x=p^k is a solution for the equation sigma(phi(x))=5(x-1). See comment lines of the sequence A093034.
%e p=30823866178561 is prime and sigma(p-1)/(p-1)=5, so p is in the sequence.
%Y Cf. A027687, A093034, A171263, A171265.
%K fini,full,nonn
%O 1,1
%A _M. F. Hasler_ and _Farideh Firoozbakht_, Apr 15 2010
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