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A169822 Numbers n such that A(n+1) = A(n) + 1, where A() = A005101() are the abundant numbers. 5
1432, 1487, 1849, 2742, 5380, 5434, 6474, 6786, 9752, 10674, 12311, 14115, 14557, 15237, 17266, 17558, 18987, 19138, 19761, 20110, 20259, 20343, 20967, 20997, 22262, 22735, 24342, 25650, 26003, 26471, 27122, 27721, 28914, 28968, 29741 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A096399 is the main entry for this sequence.

LINKS

Muniru A Asiru, Table of n, a(n) for n = 1..7000

MAPLE

with(numtheory): A:=select(n->sigma(n)>2*n, [$1..150000]):

  a:=select(j->A[j+1]=A[j]+1, [$1..nops(A)-1]); # Muniru A Asiru, Jun 10 2018

MATHEMATICA

fQ[n_] := DivisorSigma[1, n] > 2 n; lst = {}; c = 0; k = 1; While[k < 125000, If[fQ@k, c++; If[fQ[k - 1], AppendTo[lst, c - 1]]]; k++ ]; lst (* Robert G. Wilson v, Jun 11 2010 *)

PROG

(GAP) A:=Filtered([1..150000], n->Sigma(n)>2*n);;

  a:=Filtered([1..Length(A)-1], i->A[i+1]=A[i]+1); # Muniru A Asiru, Jun 10 2018

CROSSREFS

Cf. A005101, A096399.

Sequence in context: A151996 A208628 A205070 * A114083 A143475 A245948

Adjacent sequences:  A169819 A169820 A169821 * A169823 A169824 A169825

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, May 29 2010

EXTENSIONS

a(10) onwards from Robert G. Wilson v, Jun 11 2010

STATUS

approved

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Last modified December 3 12:20 EST 2020. Contains 338902 sequences. (Running on oeis4.)