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A086929 a(1) = 1, a(n) = n times (the digit reversal of the (n-1)-th partial sum). 1
1, 2, 9, 84, 345, 864, 35217, 180504, 5586408, 43430850, 530676234, 9780239700, 1055666381913, 18372986892414, 818136466402365, 314063593211808, 139031163059145687, 9080662161749058738, 64855015790195124351 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert Israel, Table of n, a(n) for n = 1..438

EXAMPLE

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

MAPLE

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

  L:= convert(n, base, 10);

  add(L[-i]*10^(i-1), i=1..nops(L))

end proc:

A[1]:= 1: S:= 1:

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

seq(A[i], i=1..20); # Robert Israel, Jun 02 2020

CROSSREFS

Sequence in context: A323769 A296581 A069234 * A193466 A262011 A120959

Adjacent sequences:  A086926 A086927 A086928 * A086930 A086931 A086932

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Sep 19 2003

EXTENSIONS

More terms from Ray Chandler, Sep 23 2003

STATUS

approved

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Last modified June 16 18:51 EDT 2021. Contains 345067 sequences. (Running on oeis4.)