A341889 a(n) is the smallest positive integer k > 1 such that n + k divides n^n + k, or 0 if no such k exists.

2, 0, 3, 2, 3, 4, 2, 6, 3, 5, 4, 10, 2, 12, 5, 2, 3, 16, 2, 18, 3, 4, 10, 22, 3, 24, 9, 8, 6, 28, 2, 30, 7, 17, 5, 6, 2, 36, 9, 5, 3, 40, 6, 42, 3, 4, 22, 46, 2, 20, 4, 16, 7, 52, 2, 14, 3, 5, 28, 58, 2, 60, 9, 8, 3, 9, 2, 66, 11, 20, 4, 70, 3, 72, 20, 14, 3, 8, 5, 78, 4, 32, 40, 82, 2, 24, 29, 11, 3, 88, 2, 6, 7, 23

Offset

1,1

Comments

k > 1 is needed in the definition as n+1 divides n^n+1 for all odd n. - Chai Wah Wu, Jun 04 2021

Links

Seiichi Manyama, Table of n, a(n) for n = 1..10000

Mathematica

a[n_] := Module[{k = 2}, While[! Divisible[n^n + k, n + k], k++]; k]; Array[a, 100, 3] (* Amiram Eldar, Jun 04 2021 *)

Prog

(PARI) a(n) = if(n==2, 0, my(k=2); while((n^n+k)%(n+k)!=0, k++); k);

Crossrefs

Cf. A242789, A242801, A242899, A301941, A341760, A341844, A341890, A341902.

Sequence in context: A243403 A051613 A173291 * A078031 A077961 A077962

Adjacent sequences: A341886 A341887 A341888 * A341890 A341891 A341892

Keyword

nonn

Author

Seiichi Manyama, Jun 04 2021

Status

approved