A359014 a(n) is the index of the smallest n-gonal number with exactly n prime factors (counted with multiplicity).

7, 4, 11, 50, 60, 22, 315, 264, 1295, 256, 315, 4480, 4727, 2634, 25123, 8192, 15903, 18432, 314315, 368640, 1859975, 95326, 2068659, 3145728, 2181039, 1028412, 23612379, 83886080, 18512791, 72421650, 536870912, 251658240

Offset

3,1

Links

Table of n, a(n) for n=3..34.

Eric Weisstein's World of Mathematics, Prime Factor

Eric Weisstein's World of Mathematics, Polygonal Number

Prog

(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

Crossrefs

Cf. A358321, A358863.

Sequence in context: A335166 A165415 A069199 * A138339 A107827 A070406

Adjacent sequences: A359011 A359012 A359013 * A359015 A359016 A359017

Keyword

nonn,more

Author

Ilya Gutkovskiy, Dec 12 2022

Extensions

a(29)-a(34) from Daniel Suteu, Dec 12 2022

Status

approved