OFFSET
0,3
COMMENTS
A pair of positive integers is divisible if the first divides the second, and is a binary containment if the positions of 1's in the reversed binary expansion of the first are a subset of those in the second.
FORMULA
a(n) = A325106(n) + n.
EXAMPLE
The a(1) = 1 through a(8) = 12 pairs:
(1,1) (1,1) (1,1) (1,1) (1,1) (1,1) (1,1) (1,1)
(2,2) (1,3) (1,3) (1,3) (1,3) (1,3) (1,3)
(2,2) (2,2) (1,5) (1,5) (1,5) (1,5)
(3,3) (3,3) (2,2) (2,2) (1,7) (1,7)
(4,4) (3,3) (2,6) (2,2) (2,2)
(4,4) (3,3) (2,6) (2,6)
(5,5) (4,4) (3,3) (3,3)
(5,5) (4,4) (4,4)
(6,6) (5,5) (5,5)
(6,6) (6,6)
(7,7) (7,7)
(8,8)
MATHEMATICA
Table[Length[Select[Tuples[Range[n], 2], Divisible[#[[2]], #[[1]]]&&SubsetQ[Position[Reverse[IntegerDigits[#[[2]], 2]], 1], Position[Reverse[IntegerDigits[#1[[1]], 2]], 1]]&]], {n, 0, 30}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 28 2019
STATUS
approved