A325106
Number of divisible binary-containment pairs of positive integers up to n.
Original entry on oeis.org
0, 0, 0, 1, 1, 2, 3, 4, 4, 5, 6, 7, 8, 9, 10, 13, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 26, 27, 28, 31, 32, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 43, 44, 45, 48, 49, 50, 51, 52, 53, 56, 57, 58, 61, 63, 64, 65, 66, 67, 70, 71, 72, 77, 77, 78, 79, 80, 81
Offset: 0
The a(3) = 1 through a(12) = 8 pairs:
{1,3} {1,3} {1,3} {1,3} {1,3} {1,3} {1,3} {1,3} {1,3} {1,3}
{1,5} {1,5} {1,5} {1,5} {1,5} {1,5} {1,5} {1,5}
{2,6} {1,7} {1,7} {1,7} {1,7} {1,7} {1,7}
{2,6} {2,6} {1,9} {1,9} {1,9} {1,9}
{2,6} {2,6} {2,6} {2,6}
{2,10} {1,11} {1,11}
{2,10} {2,10}
{4,12}
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Table[Length[Select[Subsets[Range[n],{2}],Divisible[#[[2]],#[[1]]]&&SubsetQ[Position[Reverse[IntegerDigits[#[[2]],2]],1],Position[Reverse[IntegerDigits[#1[[1]],2]],1]]&]],{n,0,30}]
A325103
Number of increasing pairs of positive integers up to n with no binary carries.
Original entry on oeis.org
0, 0, 1, 1, 4, 5, 6, 6, 13, 16, 19, 20, 23, 24, 25, 25, 40, 47, 54, 57, 64, 67, 70, 71, 78, 81, 84, 85, 88, 89, 90, 90, 121, 136, 151, 158, 173, 180, 187, 190, 205, 212, 219, 222, 229, 232, 235, 236, 251, 258, 265, 268, 275, 278, 281, 282, 289, 292, 295, 296
Offset: 0
The a(2) = 1 through a(9) = 16 pairs:
{1,2} {1,2} {1,2} {1,2} {1,2} {1,2} {1,2} {1,2}
{1,4} {1,4} {1,4} {1,4} {1,4} {1,4}
{2,4} {2,4} {1,6} {1,6} {1,6} {1,6}
{3,4} {2,5} {2,4} {2,4} {1,8} {1,8}
{3,4} {2,5} {2,5} {2,4} {2,4}
{3,4} {3,4} {2,5} {2,5}
{2,8} {2,8}
{3,4} {2,9}
{3,8} {3,4}
{4,8} {3,8}
{5,8} {4,8}
{6,8} {4,9}
{7,8} {5,8}
{6,8}
{6,9}
{7,8}
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Table[Length[Select[Subsets[Range[n],{2}],Intersection[Position[Reverse[IntegerDigits[#[[1]],2]],1],Position[Reverse[IntegerDigits[#[[2]],2]],1]]=={}&]],{n,0,30}]
A325104
Number of increasing pairs of positive integers up to n with at least one binary carry.
Original entry on oeis.org
0, 0, 0, 2, 2, 5, 9, 15, 15, 20, 26, 35, 43, 54, 66, 80, 80, 89, 99, 114, 126, 143, 161, 182, 198, 219, 241, 266, 290, 317, 345, 375, 375, 392, 410, 437, 457, 486, 516, 551, 575, 608, 642, 681, 717, 758, 800, 845, 877, 918, 960, 1007, 1051, 1100, 1150, 1203
Offset: 0
The a(3) = 2 through a(8) = 15 pairs:
{1,3} {1,3} {1,3} {1,3} {1,3} {1,3}
{2,3} {2,3} {1,5} {1,5} {1,5} {1,5}
{2,3} {2,3} {1,7} {1,7}
{3,5} {2,6} {2,3} {2,3}
{4,5} {3,5} {2,6} {2,6}
{3,6} {2,7} {2,7}
{4,5} {3,5} {3,5}
{4,6} {3,6} {3,6}
{5,6} {3,7} {3,7}
{4,5} {4,5}
{4,6} {4,6}
{4,7} {4,7}
{5,6} {5,6}
{5,7} {5,7}
{6,7} {6,7}
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Table[Length[Select[Subsets[Range[n],{2}],Intersection[Position[Reverse[IntegerDigits[#[[1]],2]],1],Position[Reverse[IntegerDigits[#[[2]],2]],1]]!={}&]],{n,0,30}]
A325095
Number of subsets of {1...n} with no binary carries.
Original entry on oeis.org
1, 2, 4, 5, 10, 12, 14, 15, 30, 35, 40, 42, 47, 49, 51, 52, 104, 119, 134, 139, 154, 159, 164, 166, 181, 186, 191, 193, 198, 200, 202, 203, 406, 458, 510, 525, 577, 592, 607, 612, 664, 679, 694, 699, 714, 719, 724, 726, 778, 793, 808, 813, 828, 833, 838, 840
Offset: 0
The a(1) = 1 through a(7) = 15 subsets:
{} {} {} {} {} {} {}
{1} {1} {1} {1} {1} {1} {1}
{2} {2} {2} {2} {2} {2}
{1,2} {3} {3} {3} {3} {3}
{1,2} {4} {4} {4} {4}
{1,2} {5} {5} {5}
{1,4} {1,2} {6} {6}
{2,4} {1,4} {1,2} {7}
{3,4} {2,4} {1,4} {1,2}
{1,2,4} {2,5} {1,6} {1,4}
{3,4} {2,4} {1,6}
{1,2,4} {2,5} {2,4}
{3,4} {2,5}
{1,2,4} {3,4}
{1,2,4}
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b:= proc(n, t) option remember; `if`(n=0, 1, b(n-1, t)+
`if`(Bits[And](n, t)=0, b(n-1, Bits[Or](n, t)), 0))
end:
a:= n-> b(n, 0):
seq(a(n), n=0..63); # Alois P. Heinz, Mar 28 2019
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binpos[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
stableQ[u_,Q_]:=!Apply[Or,Outer[#1=!=#2&&Q[#1,#2]&,u,u,1],{0,1}];
Table[Length[Select[Subsets[Range[n]],stableQ[#,Intersection[binpos[#1],binpos[#2]]!={}&]&]],{n,0,10}]
A325101
Number of divisible binary-containment pairs of positive integers up to n.
Original entry on oeis.org
0, 1, 2, 4, 5, 7, 9, 11, 12, 14, 16, 18, 20, 22, 24, 28, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 53, 55, 57, 61, 63, 64, 66, 68, 70, 72, 74, 76, 79, 81, 83, 85, 87, 89, 93, 95, 97, 99, 101, 103, 107, 109, 111, 115, 118, 120, 122, 124, 126, 130, 132, 134
Offset: 0
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)
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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}]
A325097
Heinz numbers of integer partitions whose distinct parts have no binary carries.
Original entry on oeis.org
1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 16, 17, 18, 19, 21, 23, 24, 25, 26, 27, 28, 29, 31, 32, 33, 35, 36, 37, 38, 41, 42, 43, 47, 48, 49, 52, 53, 54, 56, 57, 58, 59, 61, 63, 64, 67, 69, 71, 72, 73, 74, 76, 79, 81, 83, 84, 86, 89, 95, 96, 97, 98, 99, 101
Offset: 1
Most small numbers are in the sequence, however the sequence of non-terms together with their prime indices begins:
10: {1,3}
15: {2,3}
20: {1,1,3}
22: {1,5}
30: {1,2,3}
34: {1,7}
39: {2,6}
40: {1,1,1,3}
44: {1,1,5}
45: {2,2,3}
46: {1,9}
50: {1,3,3}
51: {2,7}
55: {3,5}
60: {1,1,2,3}
62: {1,11}
65: {3,6}
66: {1,2,5}
68: {1,1,7}
70: {1,3,4}
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binpos[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
stableQ[u_,Q_]:=!Apply[Or,Outer[#1=!=#2&&Q[#1,#2]&,u,u,1],{0,1}];
Select[Range[100],stableQ[PrimePi/@First/@FactorInteger[#],Intersection[binpos[#1],binpos[#2]]!={}&]&]
A325102
Number of ordered pairs of positive integers up to n with no binary carries.
Original entry on oeis.org
0, 0, 2, 2, 8, 10, 12, 12, 26, 32, 38, 40, 46, 48, 50, 50, 80, 94, 108, 114, 128, 134, 140, 142, 156, 162, 168, 170, 176, 178, 180, 180, 242, 272, 302, 316, 346, 360, 374, 380, 410, 424, 438, 444, 458, 464, 470, 472, 502, 516, 530, 536, 550, 556, 562, 564, 578
Offset: 0
The a(2) = 2 through a(6) = 12 pairs:
(1,2) (1,2) (1,2) (1,2) (1,2) (1,2)
(2,1) (2,1) (1,4) (1,4) (1,4) (1,4)
(2,1) (2,1) (1,6) (1,6)
(2,4) (2,4) (2,1) (2,1)
(3,4) (2,5) (2,4) (2,4)
(4,1) (3,4) (2,5) (2,5)
(4,2) (4,1) (3,4) (3,4)
(4,3) (4,2) (4,1) (4,1)
(4,3) (4,2) (4,2)
(5,2) (4,3) (4,3)
(5,2) (5,2)
(6,1) (6,1)
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Table[Length[Select[Tuples[Range[n],2],Intersection[Position[Reverse[IntegerDigits[#[[1]],2]],1],Position[Reverse[IntegerDigits[#[[2]],2]],1]]=={}&]],{n,0,30}]
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