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A144728
a(n) is the smallest positive integer such that b * (Product_{k=1..n} a(k)) + 1 is prime, with a(n) > a(n-1) for n >= 2, and b = 6.
11
1, 2, 3, 5, 9, 12, 16, 22, 25, 29, 31, 35, 47, 57, 61, 66, 79, 81, 108, 114, 148, 163, 172, 185, 198, 203, 205, 236, 265, 275, 282, 294, 312, 344, 359, 377, 397, 398, 411, 427, 431, 493, 512, 589, 647, 648, 660, 708, 719, 765, 887, 911, 916, 935, 1062, 1093, 1102
OFFSET
1,2
MATHEMATICA
k = 6; a = {}; Do[If[PrimeQ[k n + 1], k = k n; AppendTo[a, n]], {n, 1, 3000}]; a
KEYWORD
nonn
AUTHOR
Artur Jasinski, Sep 19 2008
EXTENSIONS
Definition corrected by Georg Fischer, Jun 18 2021
STATUS
approved