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A274565
Numbers k such that sigma(k) == 0 (mod k+10).
2
14, 176, 1376, 3230, 3770, 6848, 114256, 125696, 544310, 561824, 740870, 2075648, 4199030, 4607296, 8436950, 33468416, 134045696, 199272950, 624032630, 1113445430, 1550860550, 85905593344, 2199001235456
OFFSET
1,1
EXAMPLE
sigma(14) mod (14 + 10) = 24 mod 24 = 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, 10);
MATHEMATICA
k = 10; Select[Range[Abs@k+1, 10^6], Mod[DivisorSigma[1, #], # + k] == 0 &] (* Vincenzo Librandi, Jul 06 2016 *)
PROG
(Magma) [n: n in [1..2*10^6] | SumOfDivisors(n) mod (n+10) eq 0 ]; // Vincenzo Librandi, Jul 06 2016
KEYWORD
nonn
AUTHOR
Paolo P. Lava, Jul 06 2016
EXTENSIONS
a(13)-a(23) from Giovanni Resta, Jul 06 2016
STATUS
approved