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A062043
Positive numbers whose product of digits is 10 times their sum.
11
459, 495, 549, 594, 945, 954, 1566, 1656, 1665, 2259, 2295, 2355, 2529, 2535, 2553, 2592, 2925, 2952, 3255, 3525, 3552, 5166, 5229, 5235, 5253, 5292, 5325, 5352, 5523, 5532, 5616, 5661, 5922, 6156, 6165, 6516, 6561, 6615, 6651, 9225, 9252, 9522
OFFSET
1,1
COMMENTS
A subsequence of A011535 as each term must include the digit 5. - Chai Wah Wu, Dec 09 2015
LINKS
EXAMPLE
594 belongs to the sequence as (5*9*4)/(5+9+4) = 180/18 = 10.
MAPLE
filter:= proc(t) local L;
L:= convert(t, base, 10);
convert(L, `*`) = 10*convert(L, `+`)
end proc:
select(filter, [$1..10^5]); # Robert Israel, Sep 11 2022
MATHEMATICA
Select[Range[10000], Times @@ IntegerDigits[ # ] == 10 Plus @@ IntegerDigits[ # ] &] - Tanya Khovanova, Dec 25 2006
PROG
(PARI) isok(n) = my(d=digits(n)); vecprod(d)==10*vecsum(d) \\ Mohammed Yaseen, Sep 11 2022
(Python)
from math import prod
def ok(n): d = list(map(int, str(n))); return prod(d) == 10*sum(d)
print([k for k in range(1, 9999) if ok(k)]) # Michael S. Branicky, Sep 11 2022
KEYWORD
nonn,base,easy
AUTHOR
Amarnath Murthy, Jun 28 2001
EXTENSIONS
More terms from Harvey P. Dale and Larry Reeves (larryr(AT)acm.org), Jul 06 2001
STATUS
approved