# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a363039 Showing 1-1 of 1 %I A363039 #18 May 19 2023 13:23:57 %S A363039 1,2,4,274,81,44 %N A363039 a(n) is the smallest tribonacci number (A000073) with exactly n divisors, or -1 if no such number exists. %C A363039 a(8) = 24, a(10) = 745527911414639917440582097294401. %C A363039 a(7), if it exists, is > A000073(200000). - _Vaclav Kotesovec_, May 17 2023 %C A363039 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 %H A363039 Attila Petho, Fifteen problems in number theory, Acta Univ. Sapientiae Math 2:1 (2010), 72-83. %H A363039 Eric Weisstein's World of Mathematics, Tribonacci Number. %H A363039 Index entries for sequences related to divisors of numbers. %Y A363039 Cf. A000005, A000073, A005179, A081979. %K A363039 nonn,more %O A363039 1,2 %A A363039 _Ilya Gutkovskiy_, May 14 2023 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE