%I #12 Mar 25 2015 14:37:00
%S 24,57,204,411,559,2004,2440,3935,6616,8640,20004,34939,55827,61009,
%T 64599,79747,87113,87269,96513,481557,621265,647532,702893,704682,
%U 797465,2000004,2385120
%N Numbers n such that antisigma(n) contains n as a substring.
%C Any number of the form 20...04, with a number of consecutive zeros not equal to 6*k+4 (with k = 0, 1, 2, 3,...), appears to belong to the sequence.
%e antisigma(24) = (24*25) / 2 - sigma(24) = 300 - 60 = 240 and 24 is a substring;
%e antisigma(57) = (57*58) / 2 - sigma(57) = 1653 - 80 = 1573 and 57 is a substring.
%p with(numtheory): P:=proc(q) local a,b,c,d,j,n;
%p for n from 1 to q do a:=n; b:=n*(n+1)/2-sigma(n); c:=ilog10(n)+1; d:=ilog10(b)+1;
%p for j from 1 to d-c+1 do if n=(b mod 10^c) then print(n); break; else b:=trunc(b/10);
%p fi; od; od; print(); end: P(10^9);
%Y Cf. A024816.
%K nonn,base
%O 1,1
%A _Paolo P. Lava_, Mar 12 2015
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