A082495 a(n) = (2^n - 1) mod n.

0, 1, 1, 3, 1, 3, 1, 7, 7, 3, 1, 3, 1, 3, 7, 15, 1, 9, 1, 15, 7, 3, 1, 15, 6, 3, 25, 15, 1, 3, 1, 31, 7, 3, 17, 27, 1, 3, 7, 15, 1, 21, 1, 15, 16, 3, 1, 15, 29, 23, 7, 15, 1, 27, 42, 31, 7, 3, 1, 15, 1, 3, 7, 63, 31, 63, 1, 15, 7, 43, 1, 63, 1, 3, 67, 15, 17, 63, 1, 15, 79, 3, 1, 63, 31, 3, 7, 79

Offset

1,4

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Formula

a(n) = A015910(n) + A048298(n) - 1.

Mathematica

Table[Mod[2^m-1, m], {m, 6!}] (* Vladimir Joseph Stephan Orlovsky, Feb 11 2010 *)

Prog

(PARI) vector(80, n, (2^n-1) %n) \\ Michel Marcus, Jan 16 2015
(Haskell)
a082495 n = a015910 n + a048298 n - 1  -- Reinhard Zumkeller, Oct 17 2015
(Python)
def A082495(n): return (m if (m:=pow(2, n, n)) else n)-1 # Chai Wah Wu, Dec 01 2022

Crossrefs

Cf. A015910, A048298.

Cf. A000079, A062173.

Sequence in context: A122410 A309790 A349619 * A329385 A200476 A380479

Adjacent sequences: A082492 A082493 A082494 * A082496 A082497 A082498

Keyword

easy,nonn

Author

Anonymous, Apr 28 2003

Status

approved