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%I M0901 #28 Jul 22 2020 11:30:37
%S 2,3,10,12,13,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,
%T 38,39,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,
%U 215,216,217,218,219,220
%N Numbers beginning with letter 't' when spelled out in English.
%C The next 179 terms are all the numbers from 221 to 399. Assuming that '1000' is spelled 'one thousand', the following terms are the numbers in the intervals [x*1000 , x*1000+999] where x runs over all elements a(1),..,a(225) occurring up to there. Then the numbers in the intervals [x*10^6, (x+1)*10^6-1] appear, where x again runs over all preceding terms. _M. F. Hasler_, Mar 23 2011
%D Archimedeans Problems Drive, Eureka, 48 (1988), pages 55, 56, 99.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%F Let g_k(x) = (x^(2k) - x^(4k) + x^(10k) - x^(11k) + x^(12k) - x^(14k) + x^(20k) - x^(40k) + x^(200k) - x^(400k))/(1-x). Then the g.f. of the characteristic function of this sequence is sum(j>=0, g_{1000^j}(x).
%K word,nonn
%O 1,1
%A _N. J. A. Sloane_.
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