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%I #6 Apr 28 2020 09:20:53
%S 0,3,6,7,8,14,15,16,17,18,19,20,21,22,37,38,39,40,41,42,43,44,45,46,
%T 47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,107,108,109,
%U 110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128
%N Complement of A072795.
%C This gives positions of those terms in A063171 which begin with digits 11... Also the elements of table A072764 which do not occur in the leftmost column. See the comment at A081292.
%F a(0)=0, a(n) = n + A014137(A081288(n)-1).
%F a(n) = A080300(A081292(n)) = A081289(n) + n - A081290(n).
%o (PARI) A014137(n) = sum(k=0, n, binomial(2*k, k)/(k+1););
%o A081288(n) = my(i=0); while(binomial(2*i, i)/(i+1) <= n, i++); i;
%o a(n) = if (n==0, 0, n + A014137(A081288(n)-1)); \\ _Michel Marcus_, Apr 28 2020
%Y Cf. A072795, A014137, A081288.
%Y Cf. A080300, A081289, A081290, A081292.
%K nonn
%O 0,2
%A _Antti Karttunen_, Mar 17 2003
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