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%I #8 Dec 24 2022 11:16:16
%S 1,2,3,4,17,27,76,220,747,2232,5719,18980,159340,437580,1672307,
%T 10891075,78604064
%N a(n) is the index of the smallest square pyramidal number with exactly n distinct prime factors.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/DistinctPrimeFactors.html">Distinct Prime Factors</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SquarePyramidalNumber.html">Square Pyramidal Number</a>
%Y Cf. A000330, A001221, A359193, A359229.
%K nonn,more
%O 0,2
%A _Ilya Gutkovskiy_, Dec 22 2022
%E a(16) from _Jon E. Schoenfield_, Dec 22 2022