A138672 a(n) = prime(n)^3 mod prime(n-1).

1, 2, 3, 1, 8, 12, 8, 7, 9, 8, 30, 27, 8, 21, 28, 4, 8, 33, 64, 8, 70, 64, 50, 67, 64, 8, 64, 8, 64, 32, 64, 85, 8, 27, 8, 65, 59, 64, 49, 43, 8, 95, 8, 64, 8, 136, 40, 64, 8, 64, 216, 8, 36, 216, 216, 216, 8, 216, 64, 8, 151, 107, 64, 8, 64, 208, 216, 326, 8, 64

Offset

2,2

Links

Harvey P. Dale, Table of n, a(n) for n = 2..1000

Example

a(1) = 1 because 3^3 = 27 = 1 mod 2.
a(2) = 2 because 5^3 = 125 = 2 mod 3.

Mathematica

Table[Mod[Prime[n]^3, Prime[n - 1]], {n, 2, 50}]
PowerMod[#[[2]], 3, #[[1]]] & /@ Partition[Prime[Range[50]], 2, 1] (* Harvey P. Dale, Apr 24 2017 *)

Prog

(PARI) a(n) = lift(Mod(prime(n), prime(n-1))^3) \\ Andrew Howroyd, Oct 29 2025

Crossrefs

Cf. prime(n)^k mod prime(n-1): A001223, A038702, this sequence (k=3), A138673, A138674, A138675, A138676, A138677, A138678, A138679, A138680, A138681.

Sequence in context: A006015 A301332 A110292 * A103749 A098435 A096294

Adjacent sequences: A138669 A138670 A138671 * A138673 A138674 A138675

Keyword

nonn

Author

Artur Jasinski, Mar 26 2008

Extensions

Offset corrected by Andrew Howroyd, Oct 29 2025

Status

approved