A200920 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

A200920

Least k such that (3^n+ k)*3^n + 1 is a prime number.

5

1, 3, 1, 5, 3, 25, 11, 5, 13, 13, 9, 7, 3, 9, 17, 7, 29, 25, 71, 49, 7, 9, 7, 9, 11, 39, 7, 25, 107, 3, 67, 59, 49, 89, 67, 29, 113, 5, 33, 7, 19, 53, 3, 5, 47, 121, 39, 7, 407, 25, 7, 215, 29, 23, 89, 5, 33, 25, 113, 45, 49, 109, 53, 17, 109, 311, 91, 145, 43

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..69.

MATHEMATICA

Table[k = 0; While[!PrimeQ[(3^n + k)*3^n + 1], k++]; k, {n, 72}]

CROSSREFS

Cf. A191617, A191618, A191619, A191620, A200921, A200922, A200923.

Sequence in context: A002323 A294640 A365671 * A290534 A242639 A117853

Adjacent sequences: A200917 A200918 A200919 * A200921 A200922 A200923

KEYWORD

nonn

AUTHOR

Michel Lagneau, Nov 24 2011

STATUS

approved