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%I #18 Feb 10 2021 01:27:49
%S 15,208,6976,8415,31815,351351,2077696,20487159,159030135,536559616,
%T 2586415095,137433972736,2199003332608
%N Numbers k such that sigma(k) == 0 (mod k+9).
%e sigma(15) mod (15 + 9) = 24 mod 24 = 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(10^9,9);
%t Select[Range[10^6], Mod[DivisorSigma[1, #], # + 9] == 0 &] (* _Michael De Vlieger_, Jul 06 2016 *)
%Y Cf. A045770, A067702, A088833, A181598, A223610, A274551-A274562, A274564-A274566.
%K nonn,more
%O 1,1
%A _Paolo P. Lava_, Jul 06 2016
%E a(7)-a(13) from _Giovanni Resta_, Jul 06 2016
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