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%I #6 Aug 23 2014 13:06:53
%S 36,396,3996,39996,399996,3999996,39999996,399999996,3999999996,
%T 39999999996,399999999996,3999999999996
%N Numbers n such that 2n+1 is the digit reversal of n+1.
%C 1. a(n) = 36 + 360 + 3600+ ...+ up to n terms. a(n) = sum of n terms of the geometric progression with the first term 36 and common ratio 10. 2. a(n) = 36*A000042(n).( the unary sequence).
%F a(n) = 4*(10^n - 1).
%e 36 + 1 = 37, 2*36 + 1 = 73.
%Y Cf. A000042.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 08 2003
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