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A132628 Numbers n for which the sum of their digits divides sigma(n). 3
1, 6, 10, 11, 15, 19, 20, 22, 24, 30, 31, 33, 35, 42, 51, 52, 60, 62, 66, 68, 71, 79, 87, 90, 100, 101, 102, 103, 104, 105, 109, 110, 112, 114, 118, 120, 123, 124, 130, 132, 136, 138, 141, 143, 145, 147, 150, 153, 160, 161, 165, 167, 168, 174, 177, 190, 194, 198 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

n=147 -> sigma(n)=1+3+7+21+49+147=228 Sum_digits(n)=1+4+7=12 -> 228/12 = 19

n=177 -> sigma(n)=1+3+59+177=240 Sum_digits(n)=1+7+7=15 -> 240/15 = 16

MAPLE

with(numtheory); P:=proc(n) local a, i, j, k, w; for i from 1 by 1 to n do w:=0; k:=i; while k>0 do w:=w+k-(trunc(k/10)*10); k:=trunc(k/10); od; j:=sigma(i)/w; if trunc(j)=j then print(i, j); fi; od; end: P(200)

MATHEMATICA

Select[Range[200], Divisible[DivisorSigma[1, #], Total[IntegerDigits[#]]]&] (* Harvey P. Dale, Dec 06 2012 *)

CROSSREFS

Cf. A007691, A054030, A132629.

Sequence in context: A107014 A206036 A349761 * A288928 A039509 A277597

Adjacent sequences: A132625 A132626 A132627 * A132629 A132630 A132631

KEYWORD

nonn,base,easy

AUTHOR

Paolo P. Lava and Giorgio Balzarotti, Aug 24 2007

STATUS

approved

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Last modified February 3 23:01 EST 2023. Contains 360045 sequences. (Running on oeis4.)