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)
-
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}]
A325105
Number of binary carry-connected subsets of {1...n}.
Original entry on oeis.org
1, 2, 3, 7, 8, 20, 48, 112, 113, 325, 777, 1737, 3709, 7741, 15869, 32253, 32254, 96538, 225798, 485702, 1006338, 2049602, 4137346, 8315266, 16697102, 33465934, 67007886, 134100366, 268301518, 536720590, 1073575118, 2147316942, 2147316943, 6441886323
Offset: 0
The a(0) = 1 through a(4) = 8 subsets:
{} {} {} {} {}
{1} {1} {1} {1}
{2} {2} {2}
{3} {3}
{1,3} {4}
{2,3} {1,3}
{1,2,3} {2,3}
{1,2,3}
-
h:= proc(n, s) local i, m; m:= n;
for i in s do m:= Bits[Or](m, i) od; {m}
end:
g:= (n, s)-> (w-> `if`(w={}, s union {n}, s minus w union
h(n, w)))(select(x-> Bits[And](n, x)>0, s)):
b:= proc(n, s) option remember; `if`(n=0,
`if`(nops(s)>1, 0, 1), b(n-1, s)+b(n-1, g(n, s)))
end:
a:= n-> b(n, {}):
seq(a(n), n=0..35); # Alois P. Heinz, Mar 31 2019
-
binpos[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
csm[s_]:=With[{c=Select[Tuples[Range[Length[s]],2],And[OrderedQ[#],UnsameQ@@#,Length[Intersection@@s[[#]]]>0]&]},If[c=={},s,csm[Sort[Append[Delete[s,List/@c[[1]]],Union@@s[[c[[1]]]]]]]]];
Table[Length[Select[Subsets[Range[n]],Length[csm[binpos/@#]]<=1&]],{n,0,10}]
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}
-
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)
-
Table[Length[Select[Tuples[Range[n],2],Intersection[Position[Reverse[IntegerDigits[#[[1]],2]],1],Position[Reverse[IntegerDigits[#[[2]],2]],1]]=={}&]],{n,0,30}]
A325123
Number of divisible pairs of positive integers up to n with no binary carries.
Original entry on oeis.org
0, 0, 1, 1, 3, 3, 4, 4, 7, 7, 9, 9, 12, 12, 13, 13, 17, 17, 19, 19, 22, 22, 23, 23, 28, 28, 29, 29, 31, 31, 32, 32, 37, 37, 39, 39, 44, 44, 45, 45, 50, 50, 52, 52, 54, 54, 55, 55, 62, 62, 64, 64, 66, 66, 68, 68, 72, 72, 73, 73, 76, 76, 77, 77, 83, 83, 85, 85
Offset: 0
The a(2) = 1 through a(11) = 9 pairs:
{1,2} {1,2} {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} {1,4} {1,4}
{2,4} {2,4} {1,6} {1,6} {1,6} {1,6} {1,6} {1,6}
{2,4} {2,4} {1,8} {1,8} {1,8} {1,8}
{2,4} {2,4} {2,4} {2,4}
{2,8} {2,8} {2,8} {2,8}
{4,8} {4,8} {4,8} {4,8}
{1,10} {1,10}
{5,10} {5,10}
-
Table[Length[Select[Tuples[Range[n],2],Divisible@@Reverse[#]&&Intersection[Position[Reverse[IntegerDigits[#[[1]],2]],1],Position[Reverse[IntegerDigits[#[[2]],2]],1]]=={}&]],{n,0,20}]
A325099
Number of binary carry-connected strict integer partitions of n.
Original entry on oeis.org
1, 1, 1, 1, 2, 2, 3, 1, 4, 5, 8, 6, 11, 11, 15, 13, 18, 20, 30, 29, 43, 49, 68, 66, 84, 94, 125, 131, 165, 184, 237, 251, 291, 315, 383, 408, 486, 536, 663, 714, 832, 912, 1104, 1195, 1405, 1554, 1877, 2046, 2348, 2559, 2998, 3256, 3730, 4084, 4793, 5230, 5938
Offset: 0
The a(1) = 1 through a(11) = 6 strict partitions (A = 10, B = 11):
(1) (2) (3) (4) (5) (6) (7) (8) (9) (A) (B)
(31) (32) (51) (53) (54) (64) (65)
(321) (62) (63) (73) (74)
(71) (72) (91) (632)
(531) (532) (731)
(541) (5321)
(631)
(721)
-
binpos[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
csm[s_]:=With[{c=Select[Tuples[Range[Length[s]],2],And[OrderedQ[#],UnsameQ@@#,Length[Intersection@@s[[#]]]>0]&]},If[c=={},s,csm[Sort[Append[Delete[s,List/@c[[1]]],Union@@s[[c[[1]]]]]]]]];
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&Length[csm[binpos/@#]]<=1&]],{n,0,30}]
A325100
Heinz numbers of strict integer partitions with no binary carries.
Original entry on oeis.org
1, 2, 3, 5, 6, 7, 11, 13, 14, 17, 19, 21, 23, 26, 29, 31, 33, 35, 37, 38, 41, 42, 43, 47, 53, 57, 58, 59, 61, 67, 69, 71, 73, 74, 79, 83, 86, 89, 95, 97, 101, 103, 106, 107, 109, 111, 113, 114, 122, 123, 127, 131, 133, 137, 139, 142, 149, 151, 157, 158, 159
Offset: 1
The sequence of terms together with their prime indices begins:
1: {}
2: {1}
3: {2}
5: {3}
6: {1,2}
7: {4}
11: {5}
13: {6}
14: {1,4}
17: {7}
19: {8}
21: {2,4}
23: {9}
26: {1,6}
29: {10}
31: {11}
33: {2,5}
35: {3,4}
37: {12}
38: {1,8}
41: {13}
42: {1,2,4}
-
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],SquareFreeQ[#]&&stableQ[PrimePi/@First/@FactorInteger[#],Intersection[binpos[#1],binpos[#2]]!={}&]&]
A325124
Number of divisible pairs of positive integers up to n with at least one binary carry.
Original entry on oeis.org
0, 1, 2, 4, 5, 7, 10, 12, 13, 16, 18, 20, 23, 25, 28, 32, 33, 35, 39, 41, 44, 48, 51, 53, 56, 59, 62, 66, 70, 72, 79, 81, 82, 86, 88, 92, 96, 98, 101, 105, 108, 110, 116, 118, 122, 128, 131, 133, 136, 139, 143, 147, 151, 153, 159, 163, 167, 171, 174, 176, 185
Offset: 0
The a(1) = 1 through a(8) = 13 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) (3,6) (3,3) (3,3)
(4,4) (3,6) (3,6)
(5,5) (4,4) (4,4)
(6,6) (5,5) (5,5)
(6,6) (6,6)
(7,7) (7,7)
(8,8)
-
Table[Length[Select[Tuples[Range[n],2],Divisible@@Reverse[#]&&Intersection[Position[Reverse[IntegerDigits[#[[1]],2]],1],Position[Reverse[IntegerDigits[#[[2]],2]],1]]!={}&]],{n,0,20}]
A307230
Number of divisible pairs of distinct positive integers up to n with at least one binary carry.
Original entry on oeis.org
0, 0, 0, 1, 1, 2, 4, 5, 5, 7, 8, 9, 11, 12, 14, 17, 17, 18, 21, 22, 24, 27, 29, 30, 32, 34, 36, 39, 42, 43, 49, 50, 50, 53, 54, 57, 60, 61, 63, 66, 68, 69, 74, 75, 78, 83, 85, 86, 88, 90, 93, 96, 99, 100, 105, 108, 111, 114, 116, 117, 125, 126, 128, 133, 133
Offset: 0
The a(3) = 1 through a(12) = 11 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}
{3,6} {2,6} {2,6} {1,9} {1,9} {1,9} {1,9}
{3,6} {3,6} {2,6} {2,6} {2,6} {2,6}
{3,6} {3,6} {3,6} {3,6}
{3,9} {3,9} {3,9} {3,9}
{2,10} {1,11} {1,11}
{2,10} {2,10}
{4,12}
{6,12}
-
Table[Length[Select[Subsets[Range[n],{2}],Divisible@@Reverse[#]&&Intersection[Position[Reverse[IntegerDigits[#[[1]],2]],1],Position[Reverse[IntegerDigits[#[[2]],2]],1]]!={}&]],{n,0,20}]
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