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
Examples
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.
Links
- Eric Weisstein's World of Mathematics, Distinct Prime Factors
- Eric Weisstein's World of Mathematics, Square Pyramidal Number
Extensions
a(16) from Jon E. Schoenfield, Dec 22 2022