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

1,2

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

Table of n, a(n) for n=1..6.

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.

Sequence in context: A058990 A343255 A262413 * A012437 A012434 A012368

Adjacent sequences: A363036 A363037 A363038 * A363040 A363041 A363042

Keyword

nonn,more

Author

Ilya Gutkovskiy, May 14 2023

Status

approved