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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
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
Sequence in context: A151996 A208628 A205070 * A114083 A143475 A245948
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 April 15 12:18 EDT 2024. Contains 371686 sequences. (Running on oeis4.)