A359229 a(n) is the smallest square pyramidal number with exactly n distinct prime factors.

1, 5, 14, 30, 1785, 6930, 149226, 3573570, 139223370, 3708968340, 62366724420, 2279301054030, 1348519628145690, 27928822496705130, 1558931949520935990, 430616881400429491950, 161887663616926971163440

Offset

0,2

Links

Table of n, a(n) for n=0..16.

Eric Weisstein's World of Mathematics, Distinct Prime Factors

Eric Weisstein's World of Mathematics, Square Pyramidal Number

Example

a(4) = 1785, because 1785 is a square pyramidal number with 4 distinct prime factors {3, 5, 7, 17} and this is the smallest such number.

Crossrefs

Cf. A000330, A001221, A156329, A359192, A359230.

Sequence in context: A166068 A070129 A359192 * A081861 A372636 A299903

Adjacent sequences: A359226 A359227 A359228 * A359230 A359231 A359232

Keyword

nonn,more

Author

Ilya Gutkovskiy, Dec 22 2022

Extensions

a(16) from Jon E. Schoenfield, Dec 22 2022

Status

approved