login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A274561 Numbers n such that sigma(n)==0 (mod n+8). 2
10, 49, 240, 550, 748, 1504, 3192, 7192, 7912, 10792, 17272, 30592, 979992, 1713592, 4526272, 8353792, 9928792, 11547352, 17999992, 89283592, 173482552, 361702144, 1081850752, 1845991216, 2146926592, 11097907192, 12985220152, 21818579968, 34357510144, 109170719992, 228354264064, 279632332792, 549746900992, 1511712719992, 2169800814592 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..35.

EXAMPLE

sigma(10) mod (10 + 8) = 18 mod 18 = 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[10^6], Mod[DivisorSigma[1, #], # + 8] == 0 &] (* Michael De Vlieger, Jul 05 2016 *)

CROSSREFS

Cf. A045770, A067702, A088833, A181598, A274551-A274560, A274562-A274566.

Sequence in context: A271662 A244864 A051947 * A253221 A222633 A061861

Adjacent sequences:  A274558 A274559 A274560 * A274562 A274563 A274564

KEYWORD

nonn

AUTHOR

Paolo P. Lava, Jul 05 2016

EXTENSIONS

a(16)-a(35) from Giovanni Resta

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 20 16:06 EDT 2018. Contains 316390 sequences. (Running on oeis4.)