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A057147 a(n) = n times sum of digits of n. 25
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
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
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: A048385 A230101 A361203 * A213630 A061205 A290934
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 April 23 20:33 EDT 2024. Contains 371916 sequences. (Running on oeis4.)