A261469 a(n) = prime(n+3) mod prime(n).

1, 2, 3, 3, 8, 10, 12, 12, 14, 12, 12, 10, 12, 16, 14, 14, 12, 12, 12, 12, 16, 18, 18, 14, 10, 8, 10, 20, 22, 24, 12, 18, 14, 18, 14, 16, 16, 16, 14, 18, 14, 16, 8, 18, 26, 28, 18, 10, 12, 12, 18, 18, 22, 18, 14, 14, 12, 12, 16, 26, 28, 20, 10, 20, 24, 30, 18, 16, 12

Offset

1,2

Links

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

Formula

a(n) = prime(n+3) mod prime(n).

Example

a(3) = 13 mod 5 = 3.

Mathematica

a[n_]:=PowerMod[Prime[n + 3], 1, Prime[n]]; Table[a[n], {n, 80}] (* Vincenzo Librandi, Aug 20 2015 *)
Mod[Last[#], First[#]]&/@Partition[Prime[Range[80]], 4, 1] (* Harvey P. Dale, Jun 23 2017 *)

Prog

(PARI) first(m)=vector(m, i, prime(i+3)%prime(i)) \\ Anders Hellström, Aug 20 2015
(Magma) [NthPrime(n+3) mod NthPrime(n): n in [1.. 70]]; // Vincenzo Librandi, Aug 20 2015

Crossrefs

Cf. A031165.

Sequence in context: A258163 A108381 A238761 * A292498 A108692 A157126

Adjacent sequences: A261466 A261467 A261468 * A261470 A261471 A261472

Keyword

nonn,easy,less

Author

Altug Alkan, Aug 20 2015

Status

approved