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 A086929 a(1) = 1, a(n) = n times (the digit reversal of the (n-1)-th partial sum). 1

%I

%S 1,2,9,84,345,864,35217,180504,5586408,43430850,530676234,9780239700,

%T 1055666381913,18372986892414,818136466402365,314063593211808,

%U 139031163059145687,9080662161749058738,64855015790195124351

%N a(1) = 1, a(n) = n times (the digit reversal of the (n-1)-th partial sum).

%H Robert Israel, <a href="/A086929/b086929.txt">Table of n, a(n) for n = 1..438</a>

%e a(5) = 5*(reversal of (1+2+9+84)) = 5*(rev(96)) = 5*69 = 345.

%p digrev:= proc(n) local L,i;

%p L:= convert(n,base,10);

%p end proc:

%p A[1]:= 1: S:= 1:

%p for n from 2 to 20 do A[n]:= n*digrev(S); S:= S + A[n] od:

%p seq(A[i],i=1..20); # _Robert Israel_, Jun 02 2020

%K base,nonn

%O 1,2

%A _Amarnath Murthy_, Sep 19 2003

%E More terms from _Ray Chandler_, Sep 23 2003

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Last modified July 31 12:29 EDT 2021. Contains 346373 sequences. (Running on oeis4.)