A185092 Divisors of 12.

1, 2, 3, 4, 6, 12

Offset

1,2

Comments

Numbers k such that j^j == j^j^j (mod k) for every j. For k <= 16, we can compute membership directly (see Mathematica code). For k > 16, we have j = 2 as a counterexample. - Eric M. Schmidt, Aug 03 2014

Links

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

Sunil K. Chebolu and Michael Mayers, What is special about the divisors of 12?, Mathematics Magazine, 86 (2013), 143-146.

Mathematica

h1[mod_] := Table[PowerMod[i, i, mod], {i, 1, mod + LCM[mod*CarmichaelLambda[mod]]}]; h2[mod_] := Table[PowerMod[i, i^i, mod], {i, 1, mod + LCM[mod*CarmichaelLambda[mod]]}]; Union[Table[If[h1[i] == h2[i], Print[i]; i], {i, 1000}]]

Crossrefs

Cf. A217290, A323383.

Sequence in context: A375169 A061941 A029505 * A384632 A218337 A335993

Adjacent sequences: A185089 A185090 A185091 * A185093 A185094 A185095

Keyword

nonn,fini,full

Author

José María Grau Ribas, Jan 23 2012

Extensions

Renamed by Andrei Zabolotskii, May 13 2026

Status

approved