A138589 a(n) = 5^n mod 4^n.

0, 1, 9, 61, 113, 53, 3337, 12589, 62945, 118117, 328441, 2690781, 9259601, 12743573, 197935593, 452807053, 2264035265, 7025209029, 35126045145, 106910748989, 809431651889, 1848135003893, 9240675019465, 28611189052909, 213424689442209, 785648470500389

Offset: 0

Author

N. J. A. Sloane, May 20 2008

Keywords

• nonn

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..1661

Crossrefs

Cf. k^n mod (k-1)^n: A002380 (k=3), A064629 (k=4), this sequence (k=5), A138649 (k=6), A139786 (k=7), A138973 (k=8), A139733 (k=9).

Programs

Mathematica

Table[PowerMod[5, n, 4^n], {n,0,50}] (* G. C. Greubel, Oct 01 2017 *)

PARI

concat([0], vector(50, n, lift(Mod(5, 4^n)^n))) \\ Michel Marcus, Oct 02 2017