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A317048 Numbers k such that both k and k + 2 are consecutive deficient numbers. 4
5, 11, 17, 19, 23, 27, 29, 35, 39, 41, 47, 53, 55, 59, 65, 69, 71, 77, 79, 83, 87, 89, 95, 99, 101, 103, 107, 111, 113, 119, 125, 131, 137, 139, 143, 149, 155, 159, 161, 167, 173, 175, 179, 185, 191, 195, 197, 199, 203, 207, 209, 215, 219, 221, 223, 227, 233 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

MAPLE

with(numtheory):  A:=select(k->sigma(k)<2*k, [$1..300]):

a:=seq(A[i], i in select(k->A[k+1]-A[k]=2, [$1..nops(A)-1]));

PROG

(GAP) A:=Filtered([1..300], k->Sigma(k)<2*k);;

a:=List(Filtered([1..Length(A)-1], i->A[i+1]-A[i]=2), j->A[j]);

CROSSREFS

Subsequence of A005100.

Numbers j such that both k and k + j are consecutive deficient numbers: A317047 (j=1), this sequence (j=2), A317049 (j=3).

Sequence in context: A239127 A220432 A266420 * A081717 A096264 A239709

Adjacent sequences:  A317045 A317046 A317047 * A317049 A317050 A317051

KEYWORD

nonn

AUTHOR

Muniru A Asiru, Aug 04 2018

STATUS

approved

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Last modified June 5 16:19 EDT 2020. Contains 334852 sequences. (Running on oeis4.)