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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
OFFSET
1,1
LINKS
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
KEYWORD
nonn
AUTHOR
Muniru A Asiru, Aug 04 2018
STATUS
approved