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A118470 Numbers n for which digitsum(n) + digitsum(n^2) + digitsum(n^3) = digitsum(n^4). 0
0, 162, 171, 351, 468, 558, 1620, 1710, 2106, 3321, 3510, 4023, 4680, 5121, 5247, 5544, 5580, 5868, 8001, 10008, 10071, 10224, 10305, 10503, 10818, 11025, 11241, 11511, 12321, 12654, 12888, 13239, 14004, 14301, 15471, 15876, 16011, 16200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..38.

EXAMPLE

a(2)=162 because s(162)=9, s(162^2)=18, s(162^3)=27, s(162^4)=54 and 9 + 18 + 27 = 54.

MATHEMATICA

Select[Range[0, 20000], Sum[i*(DigitCount[ # ][[i]] + DigitCount[ #^2][[i]] + DigitCount[ #^3][[i]]), {i, 1, 9}] == Sum[i*DigitCount[ #^4][[i]], {i, 1, 9}] &] (* Stefan Steinerberger, May 04 2006 *)

s[n_] := Plus @@ IntegerDigits@n; Select[ Range[0, 16217], s@# + s[ #^2] + s[ #^3] == s[ #^4] &] (* Robert G. Wilson v, May 04 2006 *)

PROG

(PARI) is(n)=s=sumdigits; s(n)+s(n^2)+s(n^3) == s(n^4) \\ Anders Hellström, Sep 16 2015

CROSSREFS

Cf. A007953, A004159, A004164, A055565.

Sequence in context: A232458 A214164 A273630 * A081724 A025374 A025365

Adjacent sequences:  A118467 A118468 A118469 * A118471 A118472 A118473

KEYWORD

nonn,base

AUTHOR

Luc Stevens (lms022(AT)yahoo.com), May 04 2006

EXTENSIONS

More terms from Joshua Zucker, May 11 2006

STATUS

approved

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Last modified January 27 11:44 EST 2021. Contains 340465 sequences. (Running on oeis4.)