login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A316099 Abundant numbers that differ from the next abundant number by 6. 5
12, 24, 30, 42, 48, 60, 72, 90, 114, 120, 126, 132, 144, 150, 162, 168, 180, 186, 210, 228, 234, 240, 246, 252, 264, 282, 288, 294, 312, 324, 330, 342, 354, 372, 384, 402, 408, 420, 426, 432, 450, 468, 480, 492, 504, 510, 522, 534, 552, 564, 582, 588, 594, 600 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Muniru A Asiru, Table of n, a(n) for n = 1..10000

EXAMPLE

12 is abundant, 13, 14, 15, 16 and 17 are deficient, 18 is abundant.

24 is abundant, 25, 26, 27, 28 and 29 are deficient, 30 is abundant.

MAPLE

with(numtheory):  A:=select(n->sigma(n)>2*n, [$1..800]): a:=seq(A[i], i in select(n->A[n+1]-A[n]=6, [$1..nops(A)-1]));

MATHEMATICA

q[n_] := DivisorSigma[1, n] > 2 n; Select[Range[600], q[#] && SelectFirst[# + Range[6], q] == # + 6 &] (* Giovanni Resta, Jul 01 2018 *)

PROG

(GAP) A:=Filtered([1..800], n->Sigma(n)>2*n);;  a:=List(Filtered([1..Length(A)-1], i->A[i+1]-A[i]=6), j->A[j]);

CROSSREFS

Subsequence of A005101.

Sequence in context: A108938 A085236 A068567 * A082801 A328587 A328632

Adjacent sequences:  A316096 A316097 A316098 * A316100 A316101 A316102

KEYWORD

nonn

AUTHOR

Muniru A Asiru, Jun 25 2018

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 23 20:42 EDT 2021. Contains 347617 sequences. (Running on oeis4.)