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A064221
Least k such that k*12^n +/- 1 are twin primes.
3
4, 1, 3, 19, 33, 4, 165, 35, 150, 35, 205, 35, 63, 435, 48, 4, 223, 399, 388, 149, 125, 86, 335, 491, 565, 876, 73, 250, 85, 526, 217, 139, 557, 676, 488, 629, 592, 1290, 2110, 366, 140, 2461, 6198, 6476, 2033, 751, 7258, 2054, 2275, 1345, 445
OFFSET
0,1
MATHEMATICA
Do[ k = 1; While[ ! PrimeQ[ k*12^n + 1 ] || ! PrimeQ[ k*12^n - 1 ], k++ ]; Print[ k ], {n, 0, 50} ]
lktpQ[n_]:=Module[{c=12^n, k=1}, While[!AllTrue[k*c+{1, -1}, PrimeQ], k++]; k]; Array[lktpQ, 60, 0] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jul 21 2015 *)
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Sep 21 2001
EXTENSIONS
Offset corrected by Georg Fischer, May 01 2022
STATUS
approved