A274562 Numbers k such that sigma(k) == 0 (mod k-8).

9, 10, 11, 12, 14, 17, 38, 92, 168, 170, 248, 752, 988, 2528, 2808, 8648, 12008, 34688, 63248, 117808, 526688, 531968, 820808, 1292768, 1495688, 2095208, 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

Offset

1,1

Links

Table of n, a(n) for n=1..56.

Example

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

Mathematica

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

Crossrefs

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

Sequence in context: A296704 A297137 A129849 * A258469 A360538 A173147

Adjacent sequences: A274559 A274560 A274561 * A274563 A274564 A274565

Keyword

nonn

Author

Paolo P. Lava, Jul 05 2016

Extensions

a(30)-a(56) from Giovanni Resta, Jul 05 2016

Status

approved