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A180477 Numbers n such that r*n/k is an integer. n=(x_1 x_2 ... x_r) where x_i are digits of n, k = x_1 + x_2 + ... + x_r. 3
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 15, 18, 20, 21, 22, 24, 27, 30, 33, 36, 40, 42, 44, 45, 48, 50, 51, 54, 55, 60, 63, 66, 70, 72, 77, 80, 81, 84, 88, 90, 99, 100, 102, 108, 110, 111, 112, 114, 117, 120, 126, 132 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A005349 is a subsequence of this sequence.

n * A055642(a(n)) mod A007953(a(n)) = 0. - Reinhard Zumkeller, Oct 27 2015

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

EXAMPLE

n=126, r=3, 3*126/(1+2+6)=42, so 126 belongs to this sequence.

PROG

(Haskell)

a180477 n = a180477_list !! (n-1)

a180477_list = filter (\x -> mod (x * a055642 x) (a007953 x) == 0) [1..]

-- Reinhard Zumkeller, Oct 27 2015

CROSSREFS

Cf. A005349.

Cf. A007953, A055642, subsequence of A263808.

Sequence in context: A238368 A342164 A263808 * A271239 A083970 A246088

Adjacent sequences:  A180474 A180475 A180476 * A180478 A180479 A180480

KEYWORD

base,easy,nonn

AUTHOR

Ctibor O. Zizka, Sep 07 2010

STATUS

approved

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Last modified September 16 07:19 EDT 2021. Contains 347469 sequences. (Running on oeis4.)