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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.

A322903 Odd numbers whose prime indices are all proper powers of the same number.

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%I A322903 #5 Dec 31 2018 13:18:31
%S A322903 1,3,5,7,9,11,13,17,19,21,23,25,27,29,31,37,41,43,47,49,53,57,59,61,
%T A322903 63,67,71,73,79,81,83,89,97,101,103,107,109,113,115,121,125,127,131,
%U A322903 133,137,139,147,149,151,157,159,163,167,169,171,173,179,181,189,191
%N A322903 Odd numbers whose prime indices are all proper powers of the same number.
%C A322903 A prime index of n is a number m such that prime(m) divides n.
%C A322903 A proper power of n is a number n^k for some positive integer k.
%e A322903 The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k). The sequence of all integer partitions whose Heinz numbers belong to the sequence begins: (), (2), (3), (4), (2,2), (5), (6), (7), (8), (4,2), (9), (3,3), (2,2,2), (10), (11), (12), (13), (14), (15), (4,4), (16), (8,2), (17), (18), (4,2,2), (19), (20), (21), (22), (2,2,2,2).
%t A322903 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A322903 radbase[n_]:=n^(1/GCD@@FactorInteger[n][[All,2]]);
%t A322903 Select[Range[100],And[OddQ[#],SameQ@@radbase/@primeMS[#]]&]
%Y A322903 Cf. A001597, A018819, A023894, A052410, A056239, A072720, A072721, A302593, A322900, A322901, A322902.
%K A322903 nonn
%O A322903 1,2
%A A322903 _Gus Wiseman_, Dec 30 2018