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Sums of 12 distinct powers of 2.
3

%I #12 Feb 14 2022 01:23:37

%S 4095,6143,7167,7679,7935,8063,8127,8159,8175,8183,8187,8189,8190,

%T 10239,11263,11775,12031,12159,12223,12255,12271,12279,12283,12285,

%U 12286,13311,13823,14079,14207,14271,14303,14319,14327,14331,14333

%N Sums of 12 distinct powers of 2.

%H Ivan Neretin, <a href="/A038463/b038463.txt">Table of n, a(n) for n = 1..10000</a>

%H Robert Baillie, <a href="http://arxiv.org/abs/0806.4410">Summing the curious series of Kempner and Irwin</a>, arXiv:0806.4410 [math.CA], 2008-2015. See p. 18 for Mathematica code irwinSums.m.

%F Sum_{n>=1} 1/a(n) = 1.386296350824871649202152615241744383837323713474767661902780220440945591424... (calculated using Baillie's irwinSums.m, see Links). - _Amiram Eldar_, Feb 14 2022

%t Select[Range[15000], DigitCount[#, 2, 1] == 12 &] (* _Amiram Eldar_, Feb 14 2022 *)

%Y Base 2 interpretation of A038454.

%Y Cf. A000079, A018900, A014311, A014312, A014313, A023688, A023689, A023690, A023691, A038461, A038462 (Hamming weight = 1, 2, ..., 11).

%K nonn,base,easy

%O 1,1

%A _Olivier Gérard_

%E Offset changed to 1 by _Ivan Neretin_, Feb 28 2016