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%I #21 Jun 09 2022 21:50:42
%S 1,2,4,8,11,16,21,22,31,32,41,42,44,51,61,62,64,71,81,82,84,88,91,101,
%T 102,111,121,122,124,128,131,141,142,151,161,162,164,168,171,176,181,
%U 182,191,201,202,204,211,221,222,231,241,242,244,248,251,256,261
%N Numbers belonging to a geometric sequence whose ratio is 2 and whose first term ends in 1.
%C Numbers such that A099551(n) = 1.
%C Numbers of the form 2^m * (10n + 1). - _Charles R Greathouse IV_, May 14 2014
%F a(n) = 5n + O(log n). - _Charles R Greathouse IV_, May 14 2014
%e 176 is in the sequence because it belongs to 11, 22, 44, 88, 176, with first term 11.
%e 96, which belongs to 3, 6, 12, 24, 48, 96 with first term 3, is not a term.
%o (PARI) isok(n) = ((n/2^valuation(n, 2)) % 10) == 1; \\ _Michel Marcus_, May 14 2014
%Y Cf. A099551.
%K nonn,base,easy
%O 1,2
%A _J. Lowell_, May 10 2014
%E More terms from _Michel Marcus_, May 14 2014