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 A272361 Numbers n such that (2^n + 1) / gcd(n, 2^n + 1) is not squarefree. 2
 182, 546, 910, 1274, 1638, 2002, 2366, 2730, 3094, 3458, 3822, 4186, 4550, 4914, 5278, 5642, 6006, 6370, 6734, 7098, 7462, 7826, 8190, 8554, 8918, 9282, 9646, 10010, 10374, 10738, 11102, 11466, 11830, 12194, 12558, 12922, 13286, 13650, 14014, 14378, 14742, 15106, 15470, 15834 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Odd multiples of integer A002326((q-1)/2)/2, where q is a Wieferich prime A001220. LINKS Table of n, a(n) for n=1..44. PROG (PARI) isok(n) = my(m=2^n+1); !issquarefree(m/gcd(n, m)); \\ Michel Marcus, Apr 27 2016 CROSSREFS Cf. A049096, A272359. Sequence in context: A218563 A145297 A056091 * A158553 A015883 A043463 Adjacent sequences: A272358 A272359 A272360 * A272362 A272363 A272364 KEYWORD nonn AUTHOR Thomas Ordowski, Apr 27 2016 STATUS approved

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Last modified November 30 21:14 EST 2023. Contains 367462 sequences. (Running on oeis4.)