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A175902
Values of k in A175901.
2
5, 5, 11, 4, 11, 29, 11, 25, 13, 23, 29, 34, 13, 89, 13, 51, 11, 151, 43, 89, 181, 169, 89, 29, 101, 59, 223, 111, 181, 269, 125, 29, 23, 101, 83, 35, 56, 305, 79, 113, 181, 287, 151, 155, 379, 349, 769, 545, 329, 505, 571, 37, 373, 769, 344, 91, 1121, 79, 353, 79, 985
OFFSET
1,1
PROG
(PARI) isok(n) = {pfs = factor(n^2-1)[, 1]; for (k = 2, n-1, if (factor(k^2-1)[, 1] == pfs, return (k)); ); return (0); }
lista(nn) = {for(n=2, nn, if (k = isok(n), print1(k, ", "); ); ); } \\ Michel Marcus, Nov 04 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Oct 11 2010, Oct 21 2010
EXTENSIONS
Edited by N. J. A. Sloane, Oct 14 2010
STATUS
approved