A317048 Numbers k such that both k and k + 2 are consecutive deficient numbers.

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

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