A087611 a(n) = (prime(n) - 1) mod n.

0, 0, 1, 2, 0, 0, 2, 2, 4, 8, 8, 0, 1, 0, 1, 4, 7, 6, 9, 10, 9, 12, 13, 16, 21, 22, 21, 22, 21, 22, 2, 2, 4, 2, 8, 6, 8, 10, 10, 12, 14, 12, 18, 16, 16, 14, 22, 30, 30, 28, 28, 30, 28, 34, 36, 38, 40, 38, 40, 40, 38, 44, 54, 54, 52, 52, 62, 64, 1, 68, 68, 70, 1, 2, 3, 2, 3, 6, 5, 8

Offset

1,4

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

Table[Mod[Prime[n]-1, n], {n, 80}] (* Harvey P. Dale, Oct 29 2025 *)

Prog

(Magma) [((NthPrime(n) -1) mod n): n in [1..100]]; // Vincenzo Librandi, Apr 06 2011
(PARI) a(n) = (prime(n)-1) % n; \\ Kevin Ryde, Feb 03 2023

Crossrefs

Cf. A023143 (indices of 0's).

Cf. A006093, A004648.

Sequence in context: A033737 A033747 A379769 * A282133 A338819 A153869

Adjacent sequences: A087608 A087609 A087610 * A087612 A087613 A087614

Keyword

nonn,easy

Author

Reinhard Zumkeller, Sep 11 2003

Status

approved