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%I #11 Feb 23 2015 00:24:26
%S 14,34,38,46,58,94,118,122,194,218,226,262,298,334,358,362,386,446,
%T 458,466,514,526,538,626,674,734,758,766,778,838,866,922,974,982,998,
%U 1006,1018,1082,1142,1154,1186,1238,1294,1318,1402,1418,1454,1486,1622,1642
%N These are numbers n such that the reciprocal, 1/n, is a repeating fraction whose period is n/2 - 1.
%C These numbers relate to the long period primes, those that for 1/m the period is m-1 (sequence A006883) in that by multiplying each term in the long period primes by 2, this sequence is generated.
%o (PARI) forstep(n=2, 2e3, 2, if ((setminus(Set(factor(n)[,1]), Set([2,5])) != []) && (znorder(Mod(10, n/2^valuation(n, 2)/5^valuation(n, 5))) + 1 == n/2), print1(n, ", "));); \\ _Michel Marcus_, Feb 24 2013
%Y Cf. A006883, A007732, A085837, A121090.
%K nonn,base
%O 1,1
%A _Robert Hutchins_, Mar 29 2009
%E More terms and edited by _Michel Marcus_, Feb 24 2013
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