OFFSET
1,1
COMMENTS
Values of k for the listed terms are 5, 7, 6, 9, 10, 7, 8, 7, 11, 11, 12, 12, 12, 13, 13, 15, 14, 17, 15, 18, 16, 20, 18, 19, 20, 20, 19, 22, 21, 23, 24, 25, 26, 29, 28, 28, 29, 30, 29, 30, 31, 29, 30, 33, 37, 36, 39, 39, 41, 41, ...
LINKS
Paolo P. Lava, Table of n, a(n) for n = 1..500
EXAMPLE
For 11 the value of k is 5. Aliquot parts of 10, 9, 8, 7 and 6 are: [1, 2, 5], [1, 3], [1, 2, 4], [1], [1, 2, 3]. Residues are 0 + 1 + 1 + 0 + 2 + 0 + 1 + 3 + 0 + 0 + 1 + 2 that sum up to 11.
MAPLE
with(numtheory): P:=proc(q) local a, b, j, k, n; for n from 6 to q do
a:=0; k:=0; while a<n do k:=k+1; b:=sort([op(divisors(n-k))]);
a:=a+add(n mod b[j], j=1..nops(b)-1); od;
if a=n then print(n); fi; od; end: P(10^9);
CROSSREFS
KEYWORD
nonn
AUTHOR
Paolo P. Lava, Aug 03 2017
STATUS
approved