A274562 - OEIS

%I #16 Feb 10 2021 01:28:02

%S 9,10,11,12,14,17,38,92,168,170,248,752,988,2528,2808,8648,12008,

%T 34688,63248,117808,526688,531968,820808,1292768,1495688,2095208,

%U 2112512,3477608,4495808,8419328,12026888,13192768,16102808,26347688,29322008,33653888,169371008,173631608,293947648,537116672,883927808,2147975168,2493705728,5556840416,13092865928,42783299288,69662739968,80999455688,217898810368,546409576448,1020401174528,1081071376208,1282330216448,1473186024448,1577975316488,1608005456768

%N Numbers k such that sigma(k) == 0 (mod k-8).

%e sigma(9) mod (9 - 8) = 13 mod 1 = 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,-8);

%t Select[Range[9, 10^6], Mod[DivisorSigma[1, #], # - 8] == 0 &] (* _Michael De Vlieger_, Jul 05 2016 *)

%Y Cf. A000203, A045770, A067702, A088833, A181598, A274551-A274561, A274563-A274566.

%K nonn

%O 1,1

%A _Paolo P. Lava_, Jul 05 2016

%E a(30)-a(56) from _Giovanni Resta_, Jul 05 2016