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A169663 Numbers n divisible by the sum of the digits and the sum of the squares of digits of n (in base 10). 0
1, 10, 20, 50, 100, 110, 111, 120, 133, 200, 210, 240, 315, 360, 372, 400, 420, 480, 500, 550, 630, 803, 1000, 1010, 1011, 1020, 1071, 1100, 1101, 1110, 1134, 1148, 1200, 1300, 1302, 1330, 1344, 1431, 1547, 2000, 2010, 2023, 2040, 2100, 2196, 2200, 2220 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..47.

Eric Weisstein's World of Mathematics, Digit.

FORMULA

A007953(n)|n and A003132(n)|n.

EXAMPLE

For n = 2196, 2^2 + 1^2 + 9^2 + 6^2 = 122, 2 + 1 + 9 + 6 = 18, and 2196 = 18*122 so it is divisible by both 18 and 122.

MAPLE

with(numtheory):for n from 1 to 1000000 do:l:=evalf(floor(ilog10(n))+1):n0:=n:s1:=0:s2:=0:for m from 1 to l do:q:=n0:u:=irem(q, 10):v:=iquo(q, 10):n0:=v :s1:=s1+u:s2:=s2+u^2:od:if irem(n, s1)=0 and irem(n, s2)=0 then print(n):else fi:od:

PROG

(PARI) sd2(n) = my(d=digits(n)); sum(i=1, #d, d[i]^2);

isok(n) = !(n % sumdigits(n)) && !(n % sd2(n)); \\ Michel Marcus, Dec 21 2014

CROSSREFS

Cf. A034087, A072081, A117562.

Sequence in context: A072081 A034087 A117562 * A250602 A115045 A205879

Adjacent sequences:  A169660 A169661 A169662 * A169664 A169665 A169666

KEYWORD

nonn,base

AUTHOR

Michel Lagneau, Apr 05 2010

STATUS

approved

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Last modified November 12 04:21 EST 2019. Contains 329051 sequences. (Running on oeis4.)