A359094 a(n) is the smallest square pyramidal number divisible by exactly n square pyramidal numbers.
1, 5, 30, 140, 4900, 155155, 6930, 223300, 3573570, 380380, 340889640, 1801800, 333833500, 711410700, 78963134250, 427826509110, 70836325560, 862289508080, 62366724420, 3975527876320, 2279301054030, 3422848288860, 58264695188700, 4903512426212400
Offset: 1
Keywords
Examples
a(5) = 4900, because 4900 is a square pyramidal number that has 5 square pyramidal divisors {1, 5, 14, 140, 4900} and this is the smallest such number.
Links
- Eric Weisstein's World of Mathematics, Square Pyramidal Number
- Index entries for sequences related to divisors of numbers
Extensions
a(11)-a(24) from Jon E. Schoenfield, Dec 17 2022