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Numbers k such that k = Sum_{i=1..j} Sd(k)^i, for some j>0, where Sd(k) is the sum of the digits of k.
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%I #16 May 10 2017 11:31:36

%S 1,2,3,4,5,6,7,8,9,10,12,42,90,100,120,156,1000,3615,5219,6174,9723,

%T 10000,18278,22620,47988,54240,100000,551880,837930,1000000,2000718,

%U 10000000,12204240,12356630,25137930,40358373,54066635,62193780,100000000,133878822,168751484

%N Numbers k such that k = Sum_{i=1..j} Sd(k)^i, for some j>0, where Sd(k) is the sum of the digits of k.

%C Any power of 10 (A011557) is a term of the sequence.

%C Subsequence of A005349.

%e The sum of the digits of 22620 is 2 + 2 + 6 + 2 + 0 = 12 and 12 + 12^2 + 12^3 + 12^4 = 22620.

%p S:=proc(w) local x; x:=add(x,x=convert(w,base,10)); end:

%p P:= proc(q) local a,k,n; for n from 1 to q do a:=S(n); k:=1;

%p while a<n do k:=k+1; a:=a+S(n)^k; od; if a=n then print(n); fi; od; end: P(10^8);

%Y Cf. A005349, A007953, A011557.

%K nonn,base

%O 1,2

%A _Paolo P. Lava_, May 03 2017