OFFSET
1,2
COMMENTS
Values of k for the listed items are 1, 1, 2, 2, 4, 5, 6, 7, 14, 9, 9, 7, 11, 19, 21, 13, 14, 8, 19, 25, 17, 18, 31, 19, 13, 21, 23, 29, 27, 28, 22, 31, 53, 26, 54, 55, 23, 17, 45, 38, 62, 36, 29, 63, 65, 66, 42, 40, 47, 21, 41, 44, 36, 65.
All squarefree terms > 1 are even. - Robert Israel, Aug 07 2017
LINKS
Robert Israel, Table of n, a(n) for n = 1..1000
EXAMPLE
For 34 we have that d(34) + d(2*34) + d(3*34) + d(4*34) + d(5*34) = 4 + 6 + 8 + 8 + 8 = 34.
MAPLE
with(numtheory): P:=proc(n) local a, k; a:=0; k:=0; while a<n do k:=k+1;
a:=a+tau(k*n); od; if a=n then n; fi; end: seq(P(i), i=1..2000);
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paolo P. Lava, Aug 07 2017
STATUS
approved