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A276699
Numbers n such that Sum_{q|n} 0.q is an integer where q ranges over the aliquot parts of n.
2
14, 297, 869, 1241, 1349, 1541, 1769, 1829, 1961, 2021, 82091, 88931, 98171, 100739, 105779, 111899, 116651, 122411, 125771, 130139, 135419, 139499, 150971, 152771, 157979, 158819, 165251, 169739, 173939, 174611, 177851, 182051, 183731, 188339, 189731, 193091
OFFSET
1,1
COMMENTS
Mainly numbers ending in 1 or 9.
So far Sum{q | n} 0.q is generally equal to 1 apart from 297 with 3 and 235569 with 6.
LINKS
EXAMPLE
Aliquot parts of 14 are 1, 2, 7 and 0.1 + 0.2 + 0.7 = 1;
Aliquot parts of 297 are 1, 3, 9, 11, 27, 33, 99 and 0.1 + 0.3 + 0.9 + 0.11 + 0.27 + 0.33 + 0.99 = 3;
MAPLE
with(numtheory): P:= proc(q) local a, n;
for n from 2 to q do a:=sort([op(divisors(n))]);
if type(add(a[k]/10^(ilog10(a[k])+1), k=1..nops(a)-1), integer)
then print(n); fi; od; end: P(10^9);
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Paolo P. Lava, Sep 15 2016
STATUS
approved