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Numbers m for which there exists a number 1<k=k(m)<m, such that m is in the sequence: b_1 = k, b_(n+1) = b_n<+>k, where operation <+> is defined in A206853.
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%I #16 Feb 01 2014 07:19:53

%S 4,7,9,11,13,14,16,18,21,22,24,26,28,31,33,35,39,41,44,46,47,49,50,53,

%T 55,56,57,59,61,62,63,66,70,73,79,82,83,84,89,93,94,96,97,102,104,110,

%U 111,112,115,116,118,120,121,122,124,125,126,127,129,131

%N Numbers m for which there exists a number 1<k=k(m)<m, such that m is in the sequence: b_1 = k, b_(n+1) = b_n<+>k, where operation <+> is defined in A206853.

%C It is natural to call terms of the sequence "Hamming composite numbers" and to say that m is "H-divisible" by k.

%H Alois P. Heinz, <a href="/A207017/b207017.txt">Table of n, a(n) for n = 1..10000</a>

%e 127 = b_21 for k=2, b_16 for k=4 and b_8 for k=5. Thus 127 is H-divisible by 2, 4 and 5 (and only by them).

%Y Cf. A000225, A205509, A205510, A205511, A205302, A205649, A205533, A122565, A206853, A207016.

%K nonn,base

%O 1,1

%A _Vladimir Shevelev_, Feb 14 2012