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%I #6 Dec 15 2022 13:56:24
%S 7,4,11,50,60,22,315,264,1295,256,315,4480,4727,2634,25123,8192,15903,
%T 18432,314315,368640,1859975,95326,2068659,3145728,2181039,1028412,
%U 23612379,83886080,18512791,72421650,536870912,251658240
%N a(n) is the index of the smallest n-gonal number with exactly n prime factors (counted with multiplicity).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimeFactor.html">Prime Factor</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PolygonalNumber.html">Polygonal Number</a>
%o (PARI) a(n) = if(n<3, return()); for(k=1, oo, my(t=(k*(n*k - n - 2*k + 4))\2); if(bigomega(t) == n, return(k))); \\ _Daniel Suteu_, Dec 12 2022
%Y Cf. A358321, A358863.
%K nonn,more
%O 3,1
%A _Ilya Gutkovskiy_, Dec 12 2022
%E a(29)-a(34) from _Daniel Suteu_, Dec 12 2022
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