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A057147 a(n) = n times sum of digits of n. 15
0, 1, 4, 9, 16, 25, 36, 49, 64, 81, 10, 22, 36, 52, 70, 90, 112, 136, 162, 190, 40, 63, 88, 115, 144, 175, 208, 243, 280, 319, 90, 124, 160, 198, 238, 280, 324, 370, 418, 468, 160, 205, 252, 301, 352, 405, 460, 517, 576, 637, 250, 306, 364, 424, 486, 550, 616 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

A056992(n) = A010888(a(n)). - Reinhard Zumkeller, Mar 19 2014

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

F. B. Diniz, About a new family of sequences, arXiv:1607.06082 [math.GM], 2016.

FORMULA

a(n) = n*A007953(n). - Michel Marcus, Aug 10 2014

G.f.: x * (d/dx) (1/(1 - x))*Sum_{k>=1} (x^k - x^(10^k+k) - 9*x^(10^k))/(1 - x^(10^k)). - Ilya Gutkovskiy, Mar 27 2018

MAPLE

for n from 0 to 150 do printf(`%d, `, n*add(convert(n, base, 10)[i], i=1..nops(convert(n, base, 10)))) od:

MATHEMATICA

Table[n*Total[IntegerDigits[n]], {n, 0, 100}]

PROG

(Haskell)

a057147 n = a007953 n * n  -- Reinhard Zumkeller, Mar 19 2014

(PARI) a(n) = n*sumdigits(n) \\ Franklin T. Adams-Watters, Aug 03 2014

(Python)

[n*sum([int(d) for d in str(n)]) for n in range(10**5)] # Chai Wah Wu, Aug 05 2014

CROSSREFS

Cf. A007953, A003634, A005349, A052489, A052490, A003635, A245788.

Iterations: A047892 (start=2), A047912 (start=3), A047897 (start=5), A047898 (start=6), A047899 (start=7), A047900 (start=8), A047901 (start=9), A047902 (start=11).

Sequence in context: A068522 A048385 A230101 * A213630 A061205 A290934

Adjacent sequences:  A057144 A057145 A057146 * A057148 A057149 A057150

KEYWORD

nonn,base,easy,look

AUTHOR

N. J. A. Sloane, Sep 13 2000

EXTENSIONS

More terms from James A. Sellers and Larry Reeves (larryr(AT)acm.org), Sep 13 2000

STATUS

approved

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Last modified November 20 18:21 EST 2019. Contains 329337 sequences. (Running on oeis4.)