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A201456
Least k such that (7^n + k)*7^n + 1 is a prime number.
0
3, 3, 9, 9, 3, 3, 51, 57, 101, 5, 23, 59, 51, 161, 3, 5, 93, 135, 41, 29, 57, 5, 111, 129, 113, 35, 11, 15, 107, 129, 167, 21, 11, 143, 261, 57, 137, 113, 203, 219, 53, 101, 263, 137, 309, 101, 261, 87, 99, 239, 369, 59, 123, 83, 3, 275, 227, 321, 221, 27, 81, 135, 57, 29, 17, 281, 71, 359, 27, 395, 261, 99, 21, 215, 323, 71, 63, 29
OFFSET
1,1
MATHEMATICA
Table[k = 0; While[!PrimeQ[(7^n + k)*7^n + 1], k++]; k, {n, 85}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Dec 01 2011
STATUS
approved