OFFSET
1,1
LINKS
Ivan Neretin, Table of n, a(n) for n = 1..10000
Robert Baillie, Summing the curious series of Kempner and Irwin, arXiv:0806.4410 [math.CA], 2008-2015. See p. 18 for Mathematica code irwinSums.m.
FORMULA
Sum_{n>=1} 1/a(n) = 1.386296350824871649202152615241744383837323713474767661902780220440945591424... (calculated using Baillie's irwinSums.m, see Links). - Amiram Eldar, Feb 14 2022
MATHEMATICA
Select[Range[15000], DigitCount[#, 2, 1] == 12 &] (* Amiram Eldar, Feb 14 2022 *)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
EXTENSIONS
Offset changed to 1 by Ivan Neretin, Feb 28 2016
STATUS
approved