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%I #19 Feb 10 2021 01:28:57
%S 8,272,7232,30848,516608,134094848,2146992128
%N Numbers k such that sigma(k) == 0 (mod k+7).
%e sigma(8) mod (8+7) = 15 mod 15 = 0.
%p with(numtheory); P:=proc(q,h) local n; for n from 1 to q do
%p if n+h>0 then if type(sigma(n)/(n+h),integer) then print(n); fi; fi; od; end: P(10^9,7);
%t Select[Range[10^6], Mod[DivisorSigma[1, #], # + 7] == 0 &] (* _Michael De Vlieger_, Jul 05 2016 *)
%Y Cf. A141546, A045770, A067702, A088833, A181598, A274551-A274558, A274560-A274566.
%K nonn,more
%O 1,1
%A _Paolo P. Lava_, Jul 05 2016
%E a(6)-a(7) from _Giovanni Resta_, Jul 05 2016
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