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A047902 a(1) = 11; for n > 0, a(n+1) = a(n) * sum of digits of a(n). 11

%I

%S 11,22,88,1408,18304,292864,9078784,390387712,15615508480,

%T 671466864640,38945078149120,2375649767096320,180549382299320320,

%U 12638456760952422400,960522713832384102400,67236589968266887168000

%N a(1) = 11; for n > 0, a(n+1) = a(n) * sum of digits of a(n).

%H Reinhard Zumkeller, <a href="/A047902/b047902.txt">Table of n, a(n) for n = 1..250</a>

%F a(n+1) = A057147(a(n)). - _Reinhard Zumkeller_, Mar 19 2014

%p P:=proc(n) local a,i,k,w; a:=11; print(a); for i from 1 by 1 to n do w:=0;k:=a; while k>0 do w:=w+k-(trunc(k/10)*10); k:=trunc(k/10); od; a:=a*w; print(a); od; end: P(1000); # _Paolo P. Lava_, Apr 27 2007

%o (Haskell)

%o a047902 n = a047902_list !! (n-1)

%o a047902_list = iterate a057147 11 -- _Reinhard Zumkeller_, Mar 19 2014

%Y Cf. A047892 (start=2), A047912 (start=3), A047897 (start=5), A047898 (start=6), A047899 (start=7), A047900 (start=8), A047901 (start=9).

%K easy,nonn,base

%O 1,1

%A Miklos SZABO (mike(AT)ludens.elte.hu)

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Last modified July 25 13:05 EDT 2021. Contains 346290 sequences. (Running on oeis4.)