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.

Previous Showing 11-18 of 18 results.

A151574 a(0)=1, a(1)=2; a(2^i + j) = a(j) + 2*a(j+1) for 0 <= j < 2^i.

Original entry on oeis.org

1, 2, 5, 12, 5, 12, 29, 22, 5, 12, 29, 22, 29, 70, 73, 32, 5, 12, 29, 22, 29, 70, 73, 32, 29, 70, 73, 80, 169, 216, 137, 42, 5, 12, 29, 22, 29, 70, 73, 32, 29, 70, 73, 80, 169, 216, 137, 42, 29, 70, 73, 80, 169, 216, 137, 90, 169, 216, 233, 418, 601, 490, 221, 52, 5, 12, 29, 22, 29
Offset: 0

Views

Author

N. J. A. Sloane, May 25 2009

Keywords

Comments

Equals 2*A151572 + A151703.

Crossrefs

For the recurrence a(2^i+j) = C*a(j) + D*a(j+1), a(0) = A, a(1) = B for following values of (A B C D) see: (0 1 1 1) A118977, (1 0 1 1) A151702, (1 1 1 1) A151570, (1 2 1 1) A151571, (0 1 1 2) A151572, (1 0 1 2) A151703, (1 1 1 2) A151573, (1 2 1 2) A151574, (0 1 2 1) A160552, (1 0 2 1) A151704, (1 1 2 1) A151568, (1 2 2 1) A151569, (0 1 2 2) A151705, (1 0 2 2) A151706, (1 1 2 2) A151707, (1 2 2 2) A151708.

Programs

  • Mathematica
    a = {1, 2}; Do[AppendTo[a, a[[j]] + 2 a[[j + 1]]], {i, 6}, {j, 2^i}]; a (* Ivan Neretin, Jun 28 2017 *)

A151704 a(0)=1, a(1)=0; a(2^i+j) = 2*a(j) + a(j+1) for 0 <= j < 2^i.

Original entry on oeis.org

1, 0, 2, 2, 2, 2, 6, 6, 2, 2, 6, 6, 6, 10, 18, 14, 2, 2, 6, 6, 6, 10, 18, 14, 6, 10, 18, 18, 22, 38, 50, 30, 2, 2, 6, 6, 6, 10, 18, 14, 6, 10, 18, 18, 22, 38, 50, 30, 6, 10, 18, 18, 22, 38, 50, 34, 22, 38, 54, 58, 82, 126, 130, 62, 2, 2, 6, 6, 6, 10, 18, 14, 6, 10, 18, 18, 22, 38, 50, 30, 6
Offset: 0

Views

Author

N. J. A. Sloane, Jun 06 2009

Keywords

Crossrefs

For the recurrence a(2^i+j) = C*a(j) + D*a(j+1), a(0) = A, a(1) = B for following values of (A B C D) see: (0 1 1 1) A118977, (1 0 1 1) A151702, (1 1 1 1) A151570, (1 2 1 1) A151571, (0 1 1 2) A151572, (1 0 1 2) A151703, (1 1 1 2) A151573, (1 2 1 2) A151574, (0 1 2 1) A160552, (1 0 2 1) A151704, (1 1 2 1) A151568, (1 2 2 1) A151569, (0 1 2 2) A151705, (1 0 2 2) A151706, (1 1 2 2) A151707, (1 2 2 2) A151708.

Programs

  • Maple
    See A151702 for Maple code.
  • Mathematica
    a = {1, 0}; Do[AppendTo[a, 2 a[[j]] + a[[j + 1]]], {i, 6}, {j, 2^i}]; a (* Ivan Neretin, Jul 04 2017 *)

A151705 a(0)=0, a(1)=1; a(2^i+j) = 2*a(j) + 2*a(j+1) for 0 <= j < 2^i.

Original entry on oeis.org

0, 1, 2, 6, 2, 6, 16, 16, 2, 6, 16, 16, 16, 44, 64, 36, 2, 6, 16, 16, 16, 44, 64, 36, 16, 44, 64, 64, 120, 216, 200, 76, 2, 6, 16, 16, 16, 44, 64, 36, 16, 44, 64, 64, 120, 216, 200, 76, 16, 44, 64, 64, 120, 216, 200, 104, 120, 216, 256, 368, 672, 832, 552, 156, 2, 6, 16, 16, 16
Offset: 0

Views

Author

N. J. A. Sloane, Jun 06 2009

Keywords

Crossrefs

For the recurrence a(2^i+j) = C*a(j) + D*a(j+1), a(0) = A, a(1) = B for following values of (A B C D) see: (0 1 1 1) A118977, (1 0 1 1) A151702, (1 1 1 1) A151570, (1 2 1 1) A151571, (0 1 1 2) A151572, (1 0 1 2) A151703, (1 1 1 2) A151573, (1 2 1 2) A151574, (0 1 2 1) A160552, (1 0 2 1) A151704, (1 1 2 1) A151568, (1 2 2 1) A151569, (0 1 2 2) A151705, (1 0 2 2) A151706, (1 1 2 2) A151707, (1 2 2 2) A151708.

Programs

  • Maple
    See A151702 for Maple code.
  • Mathematica
    a = {0, 1}; Do[AppendTo[a, 2 a[[j]] + 2 a[[j + 1]]], {i, 6}, {j, 2^i}]; a (* Ivan Neretin, Jul 04 2017 *)

A151706 a(0)=1, a(1)=0; a(2^i+j) = 2*a(j) + 2*a(j+1) for 0 <= j < 2^i.

Original entry on oeis.org

1, 0, 2, 4, 2, 4, 12, 12, 2, 4, 12, 12, 12, 32, 48, 28, 2, 4, 12, 12, 12, 32, 48, 28, 12, 32, 48, 48, 88, 160, 152, 60, 2, 4, 12, 12, 12, 32, 48, 28, 12, 32, 48, 48, 88, 160, 152, 60, 12, 32, 48, 48, 88, 160, 152, 80, 88, 160, 192, 272, 496, 624, 424, 124, 2, 4, 12, 12, 12, 32, 48
Offset: 0

Views

Author

N. J. A. Sloane, Jun 06 2009

Keywords

Crossrefs

For the recurrence a(2^i+j) = C*a(j) + D*a(j+1), a(0) = A, a(1) = B for following values of (A B C D) see: (0 1 1 1) A118977, (1 0 1 1) A151702, (1 1 1 1) A151570, (1 2 1 1) A151571, (0 1 1 2) A151572, (1 0 1 2) A151703, (1 1 1 2) A151573, (1 2 1 2) A151574, (0 1 2 1) A160552, (1 0 2 1) A151704, (1 1 2 1) A151568, (1 2 2 1) A151569, (0 1 2 2) A151705, (1 0 2 2) A151706, (1 1 2 2) A151707, (1 2 2 2) A151708.

Programs

  • Maple
    See A151702 for Maple code.
  • Mathematica
    a = {1, 0}; Do[AppendTo[a, 2 a[[j]] + 2 a[[j + 1]]], {i, 6}, {j, 2^i}]; a (* Ivan Neretin, Jul 04 2017 *)

A151707 a(0)=1, a(1)=1; a(2^i+j) = 2*a(j) + 2*a(j+1) for 0 <= j < 2^i.

Original entry on oeis.org

1, 1, 4, 10, 4, 10, 28, 28, 4, 10, 28, 28, 28, 76, 112, 64, 4, 10, 28, 28, 28, 76, 112, 64, 28, 76, 112, 112, 208, 376, 352, 136, 4, 10, 28, 28, 28, 76, 112, 64, 28, 76, 112, 112, 208, 376, 352, 136, 28, 76, 112, 112, 208, 376, 352, 184, 208, 376, 448, 640, 1168, 1456, 976, 280
Offset: 0

Views

Author

N. J. A. Sloane, Jun 06 2009

Keywords

Comments

Equals A151705 + A151706.

Crossrefs

For the recurrence a(2^i+j) = C*a(j) + D*a(j+1), a(0) = A, a(1) = B for following values of (A B C D) see: (0 1 1 1) A118977, (1 0 1 1) A151702, (1 1 1 1) A151570, (1 2 1 1) A151571, (0 1 1 2) A151572, (1 0 1 2) A151703, (1 1 1 2) A151573, (1 2 1 2) A151574, (0 1 2 1) A160552, (1 0 2 1) A151704, (1 1 2 1) A151568, (1 2 2 1) A151569, (0 1 2 2) A151705, (1 0 2 2) A151706, (1 1 2 2) A151707, (1 2 2 2) A151708.

Programs

  • Maple
    See A151702 for Maple code.
  • Mathematica
    a = {1, 1}; Do[AppendTo[a, 2 a[[j]] + 2 a[[j + 1]]], {i, 6}, {j, 2^i}]; a (* Ivan Neretin, Jul 04 2017 *)

A151708 a(0)=1, a(1)=2; a(2^i+j)=2*a(j)+2*a(j+1) for 0 <= j < 2^i.

Original entry on oeis.org

1, 2, 6, 16, 6, 16, 44, 44, 6, 16, 44, 44, 44, 120, 176, 100, 6, 16, 44, 44, 44, 120, 176, 100, 44, 120, 176, 176, 328, 592, 552, 212, 6, 16, 44, 44, 44, 120, 176, 100, 44, 120, 176, 176, 328, 592, 552, 212, 44, 120, 176, 176, 328, 592, 552, 288, 328, 592, 704, 1008, 1840, 2288
Offset: 0

Views

Author

N. J. A. Sloane, Jun 06 2009

Keywords

Comments

Equals 2*A151705+A151706.

Crossrefs

For the recurrence a(2^i+j) = C*a(j) + D*a(j+1), a(0) = A, a(1) = B for following values of (A B C D) see: (0 1 1 1) A118977, (1 0 1 1) A151702, (1 1 1 1) A151570, (1 2 1 1) A151571, (0 1 1 2) A151572, (1 0 1 2) A151703, (1 1 1 2) A151573, (1 2 1 2) A151574, (0 1 2 1) A160552, (1 0 2 1) A151704, (1 1 2 1) A151568, (1 2 2 1) A151569, (0 1 2 2) A151705, (1 0 2 2) A151706, (1 1 2 2) A151707, (1 2 2 2) A151708.

Programs

  • Maple
    See A151702 for Maple code.
  • Mathematica
    a = {1, 2}; Do[AppendTo[a, 2 a[[j]] + 2 a[[j + 1]]], {i, 6}, {j, 2^i}]; a (* Ivan Neretin, Jul 04 2017 *)

A160573 G.f.: Product_{k >= 0} (1 + x^(2^k-1) + x^(2^k)).

Original entry on oeis.org

2, 3, 3, 3, 5, 6, 4, 3, 5, 6, 6, 8, 11, 10, 5, 3, 5, 6, 6, 8, 11, 10, 7, 8, 11, 12, 14, 19, 21, 15, 6, 3, 5, 6, 6, 8, 11, 10, 7, 8, 11, 12, 14, 19, 21, 15, 8, 8, 11, 12, 14, 19, 21, 17, 15, 19, 23, 26, 33, 40, 36, 21, 7, 3, 5, 6, 6, 8, 11, 10, 7, 8, 11, 12, 14, 19, 21, 15, 8, 8
Offset: 0

Views

Author

Hagen von Eitzen, May 20 2009

Keywords

Comments

Sequence mentioned in the Applegate-Pol-Sloane article; see Section 9, "explicit formulas." - Omar E. Pol, Sep 20 2011

Examples

			a(5) = binomial(2,0) + binomial(2,1) + binomial(3,2) + binomial(1,3) + binomial(2,4) + binomial(2,5) + ... = 1 + 2 + 3 + 0 + 0 + 0 + ... = 6
From _Omar E. Pol_, Jun 09 2009: (Start)
Triangle begins:
2;
3;3;
3,5,6,4;
3,5,6,6,8,11,10,5;
3,5,6,6,8,11,10,7,8,11,12,14,19,21,15,6;
3,5,6,6,8,11,10,7,8,11,12,14,19,21,15,8,8,11,12,14,19,21,17,15,19,23,26,...
(End)
		

References

  • D. Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata, Congressus Numerantium, Vol. 206 (2010), 157-191

Crossrefs

For generating functions of the form Product_{k>=c} (1+a*x^(2^k-1)+b*x^2^k) for the following values of (a,b,c) see: (1,1,0) A160573, (1,1,1) A151552, (1,1,2) A151692, (2,1,0) A151685, (2,1,1) A151691, (1,2,0) A151688 and A152980, (1,2,1) A151550, (2,2,0) A151693, (2,2,1) A151694.
Row sums of A151683. See A151687 for another version.
Cf. A151552 (g.f. has one factor fewer).
Limiting form of rows of A118977 when that sequence is written as a triangle and the initial 1 is omitted. - N. J. A. Sloane, Jun 01 2009
Cf. A139250, A139251. - Omar E. Pol, Sep 20 2011

Programs

  • Maple
    See A118977 for Maple code.
  • Mathematica
    max = 80; Product[1 + x^(2^k - 1) + x^(2^k), {k, 0, Ceiling[Log[2, max]]}] + O[x]^max // CoefficientList[#, x]& (* Jean-François Alcover, Nov 10 2016 *)

Formula

a(n) = Sum_{i >= 0} binomial(A000120(n+i),i).
For k >= 1, a(2^k-2) = k+1 and a(2^k-1) = 3; otherwise if n = 2^i + j, 0 <= j <= 2^i-3, a(n) = a(j) + a(j+1).
a(n) = 2*A151552(n) + A151552(n-1).

A151687 G.f.: x + x^2 * Product_{n>=0} (1 + x^(2^n-1) + x^(2^n)).

Original entry on oeis.org

0, 1, 2, 3, 3, 3, 5, 6, 4, 3, 5, 6, 6, 8, 11, 10, 5, 3, 5, 6, 6, 8, 11, 10, 7, 8, 11, 12, 14, 19, 21, 15, 6, 3, 5, 6, 6, 8, 11, 10, 7, 8, 11, 12, 14, 19, 21, 15, 8, 8, 11, 12, 14, 19, 21, 17, 15, 19, 23, 26, 33, 40, 36, 21, 7, 3, 5, 6, 6, 8, 11, 10, 7, 8, 11, 12, 14, 19, 21, 15, 8, 8
Offset: 0

Views

Author

N. J. A. Sloane, Jun 03 2009

Keywords

Comments

Apart from initial terms and offset, same as A160573, but has a slightly nice recurrence.

Crossrefs

Rows of triangle in A118977 converge to this.

Programs

  • Maple
    G:= x + x^2 * mul( 1 + x^(2^n-1) + x^(2^n), n=0..20);

Formula

a(0) = 0, a(2^k) = k+1; for n >= 3, if n = 2^i + j, 1 <= j < 2^i, a(n) = a(j) + a(j+1).
Previous Showing 11-18 of 18 results.