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A274561
Numbers k such that sigma(k) == 0 (mod k+8).
2
10, 49, 240, 550, 748, 1504, 3192, 7192, 7912, 10792, 17272, 30592, 979992, 1713592, 4526272, 8353792, 9928792, 11547352, 17999992, 89283592, 173482552, 361702144, 1081850752, 1845991216, 2146926592, 11097907192, 12985220152, 21818579968, 34357510144, 109170719992, 228354264064, 279632332792, 549746900992, 1511712719992, 2169800814592
OFFSET
1,1
EXAMPLE
sigma(10) mod (10 + 8) = 18 mod 18 = 0.
MAPLE
with(numtheory); P:=proc(q, h) local n; for n from 1 to q do
if n+h>0 then if type(sigma(n)/(n+h), integer) then print(n); fi; fi; od; end: P(10^9, 8);
MATHEMATICA
Select[Range[10^6], Mod[DivisorSigma[1, #], # + 8] == 0 &] (* Michael De Vlieger, Jul 05 2016 *)
KEYWORD
nonn
AUTHOR
Paolo P. Lava, Jul 05 2016
EXTENSIONS
a(16)-a(35) from Giovanni Resta
STATUS
approved