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A274557
Numbers k such that sigma(k) == 0 (mod k+6).
2
6, 24, 25, 30, 42, 54, 66, 78, 102, 114, 138, 174, 186, 222, 246, 258, 282, 304, 318, 354, 366, 402, 426, 438, 474, 498, 534, 582, 606, 618, 642, 654, 678, 762, 786, 822, 834, 894, 906, 942, 978, 1002, 1038, 1074, 1086, 1146, 1158, 1182, 1194, 1266, 1338, 1362
OFFSET
1,1
LINKS
EXAMPLE
sigma(6) mod (6+6) = 12 mod 12 = 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, 6);
MATHEMATICA
Select[Range@ 1400, Mod[DivisorSigma[1, #], # + 6] == 0 &] (* Michael De Vlieger, Jul 05 2016 *)
PROG
(PARI) is(n)=sigma(n)%(n+6)==0 \\ Charles R Greathouse IV, Jul 16 2016
KEYWORD
nonn
AUTHOR
Paolo P. Lava, Jul 05 2016
STATUS
approved