A363039 a(n) is the smallest tribonacci number (A000073) with exactly n divisors, or -1 if no such number exists.

1, 2, 4, 274, 81, 44

Offset: 1

Author

Ilya Gutkovskiy, May 14 2023

Keywords

• sign
• more

Comments

a(8) = 24, a(10) = 745527911414639917440582097294401.

a(7), if it exists, is > A000073(200000). - Vaclav Kotesovec, May 17 2023

Has an infinite number of -1's for a(p) where p is prime as A000073 only contains a finite number of perfect powers (see Theorem 1 of Petho link). - Michael S. Branicky, May 17 2023

Links

• Attila Petho, Fifteen problems in number theory, Acta Univ. Sapientiae Math 2:1 (2010), 72-83.
• Eric Weisstein's World of Mathematics, Tribonacci Number.
• Index entries for sequences related to divisors of numbers.

Crossrefs

Cf. A000005, A000073, A005179, A081979.