cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-10 of 22 results. Next

A080572 Number of ordered pairs (i,j), 0 <= i,j < n, for which (i & j) is nonzero, where & is the bitwise AND operator.

Original entry on oeis.org

0, 0, 1, 2, 7, 8, 15, 24, 37, 38, 49, 62, 81, 98, 121, 146, 175, 176, 195, 216, 247, 272, 307, 344, 387, 420, 463, 508, 559, 608, 663, 720, 781, 782, 817, 854, 909, 950, 1009, 1070, 1141, 1190, 1257, 1326, 1405, 1478, 1561, 1646, 1737, 1802, 1885, 1970, 2065, 2154
Offset: 0

Views

Author

Richard Bean, Feb 22 2003

Keywords

Comments

Conjectured to be less than or equal to lcs(n) (see sequence A063437). The value of a(2^n) is that given in Stinson and van Rees and the value of a(2^n-1) is that given in Fu, Fu and Liao. This function gives an easy way to generate these two constructions.
From Gus Wiseman, Mar 30 2019: (Start)
Also the number of ordered pairs of positive integers up to n with at least one binary carry. A binary carry of two positive integers is an overlap of the positions of 1's in their reversed binary expansion. For example, the a(2) = 1 through a(6) = 15 ordered pairs are:
(1,1) (1,1) (1,1) (1,1) (1,1)
(2,2) (1,3) (1,3) (1,3)
(2,2) (2,2) (1,5)
(2,3) (2,3) (2,2)
(3,1) (3,1) (2,3)
(3,2) (3,2) (3,1)
(3,3) (3,3) (3,2)
(4,4) (3,3)
(3,5)
(4,4)
(4,5)
(5,1)
(5,3)
(5,4)
(5,5)
(End)
a(n) is also the number of even elements in the n X n symmetric Pascal matrix. - Stefano Spezia, Nov 14 2022

References

  • C. Fu, H. Fu and W. Liao, A new construction for a critical set in special Latin squares, Proceedings of the Twenty-sixth Southeastern International Conference on Combinatorics, Graph Theory and Computing (Boca Raton, Florida, 1995), Congressus Numerantium, Vol. 110 (1995), pp. 161-166.
  • D. R. Stinson and G. H. J. van Rees, Some large critical sets, Proceedings of the Eleventh Manitoba Conference on Numerical Mathematics and Computing (Winnipeg, Manitoba, 1981), Congressus Numerantium, Vol. 34 (1982), pp. 441-456.

Crossrefs

Programs

  • Maple
    f:=proc(n) option remember; local t;
    if n <= 1 then 0
    elif (n mod 2) =  0 then 3*f(n/2)+(n/2)^2
    else t:=(n-1)/2; f(t)+2*f(t+1)+t^2-1; fi; end;
    [seq(f(n),n=0..100)]; # N. J. A. Sloane, Jul 01 2017
  • Mathematica
    a[0] = a[1] = 0; a[n_] := a[n] = If[EvenQ[n], 3*a[n/2] + n^2/4, 2*a[(n-1)/2 + 1] + a[(n-1)/2] + (1/4)*(n-1)^2 - 1];
    Array[a, 60, 0] (* Jean-François Alcover, Dec 09 2017, from Dover's formula *)
    Table[Length[Select[Tuples[Range[n-1],2],Intersection[Position[Reverse[IntegerDigits[#[[1]],2]],1],Position[Reverse[IntegerDigits[#[[2]],2]],1]]!={}&]],{n,0,20}] (* Gus Wiseman, Mar 30 2019 *)

Formula

a(2^n) = 4^n-3^n = A005061(n); a(2^n+1) = 4^n-3^n+1 = A155609(n); a(2^n-1) = 4^n-3^n-2^(n+1)+3.
a(0)=a(1)=0, a(2n) = 3a(n)+n^2, a(2n+1) = a(n)+2a(n+1)+n^2-1. This was proved by Jeremy Dover. - Ralf Stephan, Dec 08 2004
a(n) = (A325104(n) - n)/2. - Gus Wiseman, Mar 30 2019

A247935 Number of integer partitions of n whose distinct parts have no binary carries.

Original entry on oeis.org

1, 1, 2, 3, 4, 5, 8, 10, 11, 14, 18, 21, 26, 30, 38, 49, 47, 55, 66, 74, 84, 96, 110, 126, 134, 151, 171, 195, 209, 235, 272, 318, 307, 349, 377, 422, 448, 491, 534, 595, 617, 674, 734, 801, 841, 925, 998, 1098, 1118, 1219, 1299, 1418, 1476, 1591, 1711, 1865
Offset: 0

Views

Author

David S. Newman, Sep 26 2014

Keywords

Comments

From Gus Wiseman, Mar 31 2019: (Start)
A binary carry of two positive integers is an overlap of the positions of 1's in their reversed binary expansion. For example, the reversed binary expansions of 2, 5, and 8 are
{0,1}
{1,0,1}
{0,0,0,1}
and since there are no columns with more than one 1, the partition (8,5,2) is counted under a(15). The Heinz numbers of these partitions are given by A325097.
(End)

Examples

			From _Gus Wiseman_, Mar 30 2019: (Start)
The a(1) = 1 through a(8) = 11 partitions:
  (1)  (2)   (3)    (4)     (5)      (6)       (7)        (8)
       (11)  (21)   (22)    (41)     (33)      (43)       (44)
             (111)  (211)   (221)    (42)      (52)       (422)
                    (1111)  (2111)   (222)     (61)       (611)
                            (11111)  (411)     (421)      (2222)
                                     (2211)    (2221)     (4211)
                                     (21111)   (4111)     (22211)
                                     (111111)  (22111)    (41111)
                                               (211111)   (221111)
                                               (1111111)  (2111111)
                                                          (11111111)
(End)
		

Crossrefs

Programs

  • Maple
    with(Bits):
    b:= proc(n, i, t) option remember; `if`(n=0, 1, `if`(i<1, 0,
          b(n, i-1, t) +`if`(i>n or And(t, i)>0, 0,
          add(b(n-i*j, i-1, Or(t, i)), j=1..n/i))))
        end:
    a:= n-> b(n$2, 0):
    seq(a(n), n=0..80);  # Alois P. Heinz, Dec 28 2014
  • Mathematica
    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[IntegerPartitions[n],stableQ[#,Intersection[binpos[#1],binpos[#2]]!={}&]&]],{n,0,20}] (* Gus Wiseman, Mar 30 2019 *)
    b[n_, i_, t_] := b[n, i, t] = If[n == 0, 1, If[i < 1, 0, b[n, i - 1, t] + If[i > n || BitAnd[t, i] > 0, 0, Sum[b[n - i*j, i - 1, BitOr[t, i]], {j, 1, n/i}]]]];
    a[n_] := b[n, n, 0];
    a /@ Range[0, 80] (* Jean-François Alcover, May 23 2021, after Alois P. Heinz *)

Extensions

More terms from Alois P. Heinz, Oct 15 2014
Name edited by Gus Wiseman, Mar 31 2019

A325096 Number of maximal subsets of {1...n} with no binary carries.

Original entry on oeis.org

1, 1, 1, 2, 2, 3, 4, 5, 5, 7, 9, 10, 12, 13, 14, 15, 15, 20, 25, 27, 32, 34, 36, 37, 42, 44, 46, 47, 49, 50, 51, 52, 52, 67, 82, 87, 102, 107, 112, 114, 129, 134, 139, 141, 146, 148, 150, 151, 166, 171, 176, 178, 183, 185, 187, 188, 193, 195, 197, 198, 200, 201
Offset: 0

Views

Author

Gus Wiseman, Mar 27 2019

Keywords

Comments

A binary carry of two positive integers is an overlap of the positions of 1's in their reversed binary expansion.

Examples

			The a(1) = 1 through a(9) = 7 maximal subsets:
  {1}  {12}  {3}   {34}   {25}   {16}   {7}    {78}    {69}
             {12}  {124}  {34}   {25}   {16}   {168}   {78}
                          {124}  {34}   {25}   {258}   {168}
                                 {124}  {34}   {348}   {249}
                                        {124}  {1248}  {258}
                                                       {348}
                                                       {1248}
		

Crossrefs

Programs

  • Mathematica
    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}];
    maxim[s_]:=Complement[s,Last/@Select[Tuples[s,2],UnsameQ@@#&&SubsetQ@@#&]];
    Table[Length[maxim[Select[Subsets[Range[n]],stableQ[#,Intersection[binpos[#1],binpos[#2]]!={}&]&]]],{n,0,10}]

Formula

a(2^n - 1) = A000110(n).

Extensions

a(15)-a(61) from Alois P. Heinz, Mar 28 2019

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

Views

Author

Gus Wiseman, Mar 28 2019

Keywords

Comments

A binary carry of two positive integers is an overlap of the positions of 1's in their reversed binary expansion.

Examples

			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}
		

Crossrefs

Programs

  • Mathematica
    Table[Length[Select[Subsets[Range[n],{2}],Intersection[Position[Reverse[IntegerDigits[#[[1]],2]],1],Position[Reverse[IntegerDigits[#[[2]],2]],1]]=={}&]],{n,0,30}]

Formula

a(n) = A325102(n)/2.

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

Views

Author

Gus Wiseman, Mar 28 2019

Keywords

Comments

A binary carry of two positive integers is an overlap of the positions of 1's in their reversed binary expansion.
The version for ordered pairs is A080572.

Examples

			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}
		

Crossrefs

Programs

  • Mathematica
    Table[Length[Select[Subsets[Range[n],{2}],Intersection[Position[Reverse[IntegerDigits[#[[1]],2]],1],Position[Reverse[IntegerDigits[#[[2]],2]],1]]!={}&]],{n,0,30}]

Formula

a(n) = 2 * A080572(n - 2) + n.

A325098 Number of binary carry-connected integer partitions of n.

Original entry on oeis.org

1, 1, 2, 2, 4, 4, 7, 7, 13, 15, 23, 27, 42, 50, 72, 88, 125, 153, 211, 258, 349, 430, 569, 698, 914, 1119, 1444, 1765, 2252, 2745, 3470, 4214, 5276, 6387, 7934, 9568, 11800, 14181, 17379, 20818, 25351, 30264, 36668, 43633, 52589, 62394, 74872, 88576, 105818
Offset: 0

Views

Author

Gus Wiseman, Mar 28 2019

Keywords

Comments

A binary carry of two positive integers is an overlap of the positions of 1's in their reversed binary expansion. An integer partition is binary carry-connected if the graph whose vertices are the parts and whose edges are binary carries is connected.

Examples

			The a(1) = 1 through a(8) = 13 partitions:
  (1)  (2)   (3)    (4)     (5)      (6)       (7)        (8)
       (11)  (111)  (22)    (32)     (33)      (322)      (44)
                    (31)    (311)    (51)      (331)      (53)
                    (1111)  (11111)  (222)     (511)      (62)
                                     (321)     (3211)     (71)
                                     (3111)    (31111)    (332)
                                     (111111)  (1111111)  (2222)
                                                          (3221)
                                                          (3311)
                                                          (5111)
                                                          (32111)
                                                          (311111)
                                                          (11111111)
		

Crossrefs

Programs

  • Maple
    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, i, s) option remember; `if`(n=0, `if`(nops(s)>1, 0, 1),
          `if`(i<1, 0, b(n, i-1, s)+ b(n-i, min(i, n-i), g(i, s))))
        end:
    a:= n-> b(n$2, {}):
    seq(a(n), n=0..50);  # Alois P. Heinz, Mar 29 2019
  • Mathematica
    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],Length[csm[binpos/@#]]<=1&]],{n,0,20}]
    (* Second program: *)
    h[n_, s_] := Module[{i, m = n}, Do[m = BitOr[m, i], {i, s}]; {m}];
    g[n_, s_] := Function[w, If[w == {}, s ~Union~ {n}, (s ~Complement~ w) ~Union~
        h[n, w]]][Select[s, BitAnd[n, #] > 0&]];
    b[n_, i_, s_] := b[n, i, s] = If[n == 0, If[Length[s] > 1, 0, 1],
        If[i < 1, 0, b[n, i - 1, s] + b[n - i, Min[i, n - i], g[i, s]]]];
    a[n_] := b[n, n, {}];
    a /@ Range[0, 50] (* Jean-François Alcover, May 11 2021, after Alois P. Heinz *)

Extensions

a(21)-a(48) from Alois P. Heinz, Mar 29 2019

A325110 Number of strict integer partitions of n with no binary containments.

Original entry on oeis.org

1, 1, 1, 2, 1, 2, 2, 5, 2, 3, 2, 6, 3, 6, 7, 15, 8, 10, 6, 13, 6, 10, 12, 23, 13, 16, 16, 26, 21, 30, 37, 60, 43, 52, 42, 60, 42, 50, 54, 81, 59, 60, 66, 80, 74, 86, 108, 145, 119, 125, 126, 144, 134, 140, 170, 208, 189, 193, 221, 248, 253, 292, 323, 435, 392
Offset: 0

Views

Author

Gus Wiseman, Mar 28 2019

Keywords

Comments

A pair of positive integers is a binary containment if the positions of 1's in the reversed binary expansion of the first are a subset of the positions of 1's in the reversed binary expansion of the second.

Examples

			The a(1) = 1 through a(12) = 3 partitions (A = 10, B = 11, C = 12):
  (1)  (2)  (3)   (4)  (5)   (6)   (7)    (8)   (9)   (A)   (B)    (C)
            (21)       (41)  (42)  (43)   (53)  (63)  (82)  (65)   (84)
                                   (52)         (81)        (83)   (93)
                                   (61)                     (92)
                                   (421)                    (A1)
                                                            (821)
		

Crossrefs

Programs

  • Mathematica
    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[IntegerPartitions[n],UnsameQ@@#&&stableQ[#,SubsetQ[binpos[#1],binpos[#2]]&]&]],{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

Views

Author

Gus Wiseman, Mar 27 2019

Keywords

Comments

A binary carry of two positive integers is an overlap of the positions of 1's in their reversed binary expansion. For example, the binary representations of {2,5,8} are:
2 = 10,
5 = 101,
8 = 1000,
and since there are no columns with more than one 1, {2,5,8} is counted under a(8).

Examples

			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}
		

Crossrefs

Programs

  • Maple
    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
  • Mathematica
    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}]

Formula

a(2^n - 1) = A000110(n + 1).

Extensions

a(16)-a(55) from Alois P. Heinz, Mar 28 2019

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

Views

Author

Gus Wiseman, Mar 27 2019

Keywords

Comments

A binary carry of two positive integers is an overlap of the positions of 1's in their reversed binary expansion.
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1) * ... * prime(y_k), so these are numbers whose distinct prime indices have no binary carries.

Examples

			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}
		

Crossrefs

Programs

  • Mathematica
    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]]!={}&]&]

A050314 Triangle: a(n,k) = number of partitions of n whose xor-sum is k.

Original entry on oeis.org

1, 0, 1, 1, 0, 1, 0, 1, 0, 2, 2, 0, 2, 0, 1, 0, 3, 0, 2, 0, 2, 4, 0, 3, 0, 2, 0, 2, 0, 4, 0, 4, 0, 2, 0, 5, 6, 0, 5, 0, 4, 0, 6, 0, 1, 0, 8, 0, 6, 0, 8, 0, 6, 0, 2, 10, 0, 9, 0, 11, 0, 8, 0, 2, 0, 2, 0, 11, 0, 14, 0, 12, 0, 12, 0, 2, 0, 5, 16, 0, 18, 0, 15, 0, 16, 0, 4, 0, 6, 0, 2, 0, 23, 0, 20, 0, 20, 0, 19, 0, 8, 0, 6, 0, 5
Offset: 0

Views

Author

Christian G. Bower, Sep 15 1999

Keywords

Examples

			Triangle: a(n,k) begins:
   1;
   0,  1;
   1,  0,  1;
   0,  1,  0,  2;
   2,  0,  2,  0,  1;
   0,  3,  0,  2,  0,  2;
   4,  0,  3,  0,  2,  0,  2;
   0,  4,  0,  4,  0,  2,  0,  5;
   6,  0,  5,  0,  4,  0,  6,  0, 1;
   0,  8,  0,  6,  0,  8,  0,  6, 0, 2;
  10,  0,  9,  0, 11,  0,  8,  0, 2, 0, 2;
   0, 11,  0, 14,  0, 12,  0, 12, 0, 2, 0, 5;
  16,  0, 18,  0, 15,  0, 16,  0, 4, 0, 6, 0, 2;
  ...
		

Crossrefs

a(2n,0) = A048833(n). a(2n+1,1) = A050316(n). a(n,n) = A050315(n).
Row sums give A000041.
a(4n,2n) gives A370874.

Programs

  • Maple
    with(Bits):
    b:= proc(n, i, k) option remember; `if`(n=0, x^k, `if`(i<1, 0,
          add(b(n-i*j, i-1, `if`(j::even, k, Xor(i, k))), j=0..n/i)))
        end:
    T:= n-> (p-> seq(coeff(p, x, i), i=0..n))(b(n$2, 0)):
    seq(T(n), n=0..20);  # Alois P. Heinz, Dec 01 2015
  • Mathematica
    b[n_, i_, k_] := b[n, i, k] = If[n==0, x^k, If[i<1, 0, Sum[b[n-i*j, i-1, If[EvenQ[j], k, BitXor[i, k]]], {j, 0, n/i}]]]; T[n_] := Function[p, Table[Coefficient[p, x, i], {i, 0, n}]][b[n, n, 0]]; Table[T[n], {n, 0, 20}] // Flatten (* Jean-François Alcover, Jan 24 2016, after Alois P. Heinz *)
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