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.

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A301298 Expansion of (1 + 4*x + 4*x^2 + 4*x^3 + x^4)/((1 - x)*(1 - x^3)).

Original entry on oeis.org

1, 5, 9, 14, 19, 23, 28, 33, 37, 42, 47, 51, 56, 61, 65, 70, 75, 79, 84, 89, 93, 98, 103, 107, 112, 117, 121, 126, 131, 135, 140, 145, 149, 154, 159, 163, 168, 173, 177, 182, 187, 191, 196, 201, 205, 210, 215, 219, 224, 229, 233, 238, 243, 247, 252, 257, 261
Offset: 0

Views

Author

N. J. A. Sloane, Mar 24 2018

Keywords

Comments

Coordination sequence for pentavalent node in the "krl" 2-D tiling (or net). (This is easily established using the "coloring book" method - see the Goodman-Strauss & Sloane link.)
Linear recurrence and g.f. confirmed by Shutov/Maleev link. - Ray Chandler, Aug 31 2023

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. See Table 2.2.1, page 66, 3rd row, second tiling.

Crossrefs

Cf. A298024.
Coordination sequences for the 20 2-uniform tilings in the order in which they appear in the Galebach catalog, together with their names in the RCSR database (two sequences per tiling): #1 krt A265035, A265036; #2 cph A301287, A301289; #3 krm A301291, A301293; #4 krl A301298, A298024; #5 krq A301299, A301301; #6 krs A301674, A301676; #7 krr A301670, A301672; #8 krk A301291, A301293; #9 krn A301678, A301680; #10 krg A301682, A301684; #11 bew A008574, A296910; #12 krh A301686, A301688; #13 krf A301690, A301692; #14 krd A301694, A219529; #15 krc A301708, A301710; #16 usm A301712, A301714; #17 krj A219529, A301697; #18 kre A301716, A301718; #19 krb A301720, A301722; #20 kra A301724, A301726.

Programs

  • Magma
    I:=[1,5,9,14,19]; [n le 5 select I[n] else Self(n-1)+Self(n-3)-Self(n-4): n in [1..80]]; // Vincenzo Librandi, Mar 26 2018
    
  • Magma
    [n eq 0 select 1 else 5*n-Floor((n+1)/3): n in [0..60]]; // Bruno Berselli, Mar 26 2018
    
  • Mathematica
    CoefficientList[Series[(x^4 + 4 x^3 + 4 x^2 + 4 x + 1) / ((1 -x) (1 - x^3)), {x, 0, 60}], x] (* Vincenzo Librandi, Mar 26 2018 *)
    LinearRecurrence[{1,0,1,-1},{1,5,9,14,19},60] (* Harvey P. Dale, Dec 30 2024 *)
  • PARI
    lista(nn) = {x='x+O('x^nn); Vec((x^4+4*x^3+4*x^2+4*x+1)/((1-x)*(1-x^3)))} \\ Altug Alkan, Mar 26 2018

Formula

G.f.: (1 + 4*x + 4*x^2 + 4*x^3 + x^4)/((1 - x)*(1 - x^3)).
a(n) = 5*n - floor((n + 1)/3) for n>0, a(0)=1. - Bruno Berselli, Mar 26 2018

A301299 Coordination sequence for node of type V1 in "krq" 2-D tiling (or net).

Original entry on oeis.org

1, 4, 8, 13, 18, 22, 26, 29, 34, 40, 44, 48, 50, 55, 62, 66, 70, 71, 76, 84, 88, 92, 92, 97, 106, 110, 114, 113, 118, 128, 132, 136, 134, 139, 150, 154, 158, 155, 160, 172, 176, 180, 176, 181, 194, 198, 202, 197, 202, 216, 220, 224, 218, 223, 238, 242, 246, 239, 244, 260, 264, 268, 260, 265, 282
Offset: 0

Views

Author

N. J. A. Sloane, Mar 25 2018

Keywords

Comments

Linear recurrence and g.f. confirmed by Shutov/Maleev link. - Ray Chandler, Aug 31 2023

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. See Table 2.2.1, page 66, bottom row, 2nd tiling.

Crossrefs

Cf. A301301.
Coordination sequences for the 20 2-uniform tilings in the order in which they appear in the Galebach catalog, together with their names in the RCSR database (two sequences per tiling): #1 krt A265035, A265036; #2 cph A301287, A301289; #3 krm A301291, A301293; #4 krl A301298, A298024; #5 krq A301299, A301301; #6 krs A301674, A301676; #7 krr A301670, A301672; #8 krk A301291, A301293; #9 krn A301678, A301680; #10 krg A301682, A301684; #11 bew A008574, A296910; #12 krh A301686, A301688; #13 krf A301690, A301692; #14 krd A301694, A219529; #15 krc A301708, A301710; #16 usm A301712, A301714; #17 krj A219529, A301697; #18 kre A301716, A301718; #19 krb A301720, A301722; #20 kra A301724, A301726.

Programs

  • Mathematica
    LinearRecurrence[{0,0,0,0,2,0,0,0,0,-1},{1,4,8,13,18,22,26,29,34,40,44},100] (* Paolo Xausa, Nov 15 2023 *)

Formula

G.f.: -(-x^10-4*x^9-8*x^8-13*x^7-18*x^6-20*x^5-18*x^4-13*x^3-8*x^2-4*x-1)/(x^10-2*x^5+1). - N. J. A. Sloane, Mar 29 2018

Extensions

a(11)-a(100) from Davide M. Proserpio, Mar 28 2018

A301301 Coordination sequence for node of type V2 in "krq" 2-D tiling (or net).

Original entry on oeis.org

1, 4, 8, 12, 16, 20, 25, 30, 34, 39, 43, 47, 53, 56, 60, 65, 68, 75, 78, 81, 87, 89, 97, 100, 102, 109, 110, 119, 122, 123, 131, 131, 141, 144, 144, 153, 152, 163, 166, 165, 175, 173, 185, 188, 186, 197, 194, 207, 210, 207, 219, 215, 229, 232, 228, 241, 236, 251, 254, 249, 263, 257, 273, 276, 270
Offset: 0

Views

Author

N. J. A. Sloane, Mar 25 2018

Keywords

Comments

Linear recurrence and g.f. confirmed by Shutov/Maleev link. - Ray Chandler, Aug 31 2023

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. See Table 2.2.1, page 66, bottom row, 2nd tiling.

Crossrefs

Cf. A301299.
Coordination sequences for the 20 2-uniform tilings in the order in which they appear in the Galebach catalog, together with their names in the RCSR database (two sequences per tiling): #1 krt A265035, A265036; #2 cph A301287, A301289; #3 krm A301291, A301293; #4 krl A301298, A298024; #5 krq A301299, A301301; #6 krs A301674, A301676; #7 krr A301670, A301672; #8 krk A301291, A301293; #9 krn A301678, A301680; #10 krg A301682, A301684; #11 bew A008574, A296910; #12 krh A301686, A301688; #13 krf A301690, A301692; #14 krd A301694, A219529; #15 krc A301708, A301710; #16 usm A301712, A301714; #17 krj A219529, A301697; #18 kre A301716, A301718; #19 krb A301720, A301722; #20 kra A301724, A301726.

Programs

  • Mathematica
    LinearRecurrence[{0,0,0,0,2,0,0,0,0,-1},{1,4,8,12,16,20,25,30,34,39,43,47,53,56,60,65,68,75},100] (* Paolo Xausa, Nov 15 2023 *)

Formula

G.f. = -(x^17+x^16+x^15+2*x^14-x^12-x^11-4*x^10-7*x^9-10*x^8-14*x^7-17*x^6-18*x^5-16*x^4-12*x^3-8*x^2-4*x-1)/(x^10-2*x^5+1). - N. J. A. Sloane, Mar 29 2018

Extensions

a(11)-a(100) from Davide M. Proserpio, Mar 28 2018

A301670 Coordination sequence for node of type V1 in "krr" 2-D tiling (or net).

Original entry on oeis.org

1, 4, 8, 12, 16, 22, 26, 26, 36, 36, 44, 42, 54, 50, 64, 56, 72, 66, 82, 70, 92, 80, 100, 86, 110, 94, 120, 100, 128, 110, 138, 114, 148, 124, 156, 130, 166, 138, 176, 144, 184, 154, 194, 158, 204, 168, 212, 174, 222, 182, 232, 188, 240, 198, 250, 202, 260
Offset: 0

Views

Author

N. J. A. Sloane, Mar 25 2018

Keywords

Comments

Linear recurrence and g.f. confirmed by Shutov/Maleev link. - Ray Chandler, Aug 30 2023

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. See Table 2.2.1, page 67, bottom row, 1st tiling.

Crossrefs

Cf. A301672.
Coordination sequences for the 20 2-uniform tilings in the order in which they appear in the Galebach catalog, together with their names in the RCSR database (two sequences per tiling): #1 krt A265035, A265036; #2 cph A301287, A301289; #3 krm A301291, A301293; #4 krl A301298, A298024; #5 krq A301299, A301301; #6 krs A301674, A301676; #7 krr A301670, A301672; #8 krk A301291, A301293; #9 krn A301678, A301680; #10 krg A301682, A301684; #11 bew A008574, A296910; #12 krh A301686, A301688; #13 krf A301690, A301692; #14 krd A301694, A219529; #15 krc A301708, A301710; #16 usm A301712, A301714; #17 krj A219529, A301697; #18 kre A301716, A301718; #19 krb A301720, A301722; #20 kra A301724, A301726.

Programs

  • Mathematica
    LinearRecurrence[{-1,0,1,2,1,0,-1,-1},{1,4,8,12,16,22,26,26,36,36},100] (* Paolo Xausa, Nov 15 2023 *)
  • PARI
    \\ See Links section.

Formula

Based on the b-file, the g.f. appears to be
(-2*x^9+x^8+5*x^7+16*x^6+21*x^5+22*x^4+19*x^3+12*x^2+5*x+1) / ((1+x)*(1-x^3)*(1-x^4)). - N. J. A. Sloane, Mar 25 2018
a(n) = (75*n + 9*(n - 4)*(-1)^n + 18*A163805(n+2) - 12*A049347(n+2))/18 for n >1. - Stefano Spezia, Jun 08 2024

Extensions

More terms from Rémy Sigrist, Mar 25 2018

A301672 Coordination sequence for node of type V2 in "krr" 2-D tiling (or net).

Original entry on oeis.org

1, 4, 8, 13, 17, 20, 25, 30, 33, 37, 42, 46, 50, 54, 58, 63, 67, 70, 75, 80, 83, 87, 92, 96, 100, 104, 108, 113, 117, 120, 125, 130, 133, 137, 142, 146, 150, 154, 158, 163, 167, 170, 175, 180, 183, 187, 192, 196, 200, 204, 208, 213, 217, 220, 225, 230, 233
Offset: 0

Views

Author

N. J. A. Sloane, Mar 25 2018

Keywords

Comments

Linear recurrence and g.f. confirmed by Shutov/Maleev link. - Ray Chandler, Aug 30 2023

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. See Table 2.2.1, page 67, bottom row, 1st tiling.

Crossrefs

Cf. A301670.
Coordination sequences for the 20 2-uniform tilings in the order in which they appear in the Galebach catalog, together with their names in the RCSR database (two sequences per tiling): #1 krt A265035, A265036; #2 cph A301287, A301289; #3 krm A301291, A301293; #4 krl A301298, A298024; #5 krq A301299, A301301; #6 krs A301674, A301676; #7 krr A301670, A301672; #8 krk A301291, A301293; #9 krn A301678, A301680; #10 krg A301682, A301684; #11 bew A008574, A296910; #12 krh A301686, A301688; #13 krf A301690, A301692; #14 krd A301694, A219529; #15 krc A301708, A301710; #16 usm A301712, A301714; #17 krj A219529, A301697; #18 kre A301716, A301718; #19 krb A301720, A301722; #20 kra A301724, A301726.

Programs

  • Mathematica
    LinearRecurrence[{1,-1,2,-1,1,-1},{1,4,8,13,17,20,25},100] (* Paolo Xausa, Nov 15 2023 *)
  • PARI
    \\ See Links section.

Formula

Based on the b-file, the g.f. appears to be
(x^3+2*x^2+x+1)*(x^3+x^2+2*x+1) / ((1-x)*(1+x^2)*(1-x^3)). - N. J. A. Sloane, Mar 25 2018
a(n) = (75*n - 9*A163805(n+2) + 6*A049347(n+2))/18 for n > 0. - Stefano Spezia, Jun 08 2024

Extensions

More terms from Rémy Sigrist, Mar 25 2018

A301674 Coordination sequence for node of type V1 in "krs" 2-D tiling (or net).

Original entry on oeis.org

1, 4, 8, 14, 16, 26, 22, 34, 36, 38, 44, 54, 46, 62, 64, 62, 72, 82, 70, 90, 92, 86, 100, 110, 94, 118, 120, 110, 128, 138, 118, 146, 148, 134, 156, 166, 142, 174, 176, 158, 184, 194, 166, 202, 204, 182, 212, 222, 190, 230, 232, 206, 240, 250, 214, 258, 260
Offset: 0

Views

Author

N. J. A. Sloane, Mar 25 2018

Keywords

Comments

Linear recurrence and g.f. confirmed by Shutov/Maleev link. - Ray Chandler, Aug 31 2023

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. See Table 2.2.1, page 67, bottom row, 2nd tiling.

Crossrefs

Cf. A301676.
Coordination sequences for the 20 2-uniform tilings in the order in which they appear in the Galebach catalog, together with their names in the RCSR database (two sequences per tiling): #1 krt A265035, A265036; #2 cph A301287, A301289; #3 krm A301291, A301293; #4 krl A301298, A298024; #5 krq A301299, A301301; #6 krs A301674, A301676; #7 krr A301670, A301672; #8 krk A301291, A301293; #9 krn A301678, A301680; #10 krg A301682, A301684; #11 bew A008574, A296910; #12 krh A301686, A301688; #13 krf A301690, A301692; #14 krd A301694, A219529; #15 krc A301708, A301710; #16 usm A301712, A301714; #17 krj A219529, A301697; #18 kre A301716, A301718; #19 krb A301720, A301722; #20 kra A301724, A301726.

Programs

  • Mathematica
    LinearRecurrence[{-1,0,2,2,0,-1,-1},{1,4,8,14,16,26,22,34,36},100] (* Paolo Xausa, Nov 15 2023 *)
  • PARI
    See Links section.

Formula

(a) G.f. = -(2*x^8-x^7-5*x^6-18*x^5-20*x^4-20*x^3-12*x^2-5*x-1)/((x+1)*(x-1)^2*(x^2+x+1)^2). (b) Satisfies the recurrence {( - 2*n^5 - 13*n^4 - 22*n^3 + 7*n^2 + 30*n)*a(n) + ( - 2*n^5 - 13*n^4 - 25*n^3 + n^2 + 39*n)*a(n + 1) + ( - 6*n^2 + 6*n)*a(n + 2) + (2*n^5 + 7*n^4 + 7*n^3 - 7*n^2 - 9*n)*a(n + 3) + (2*n^5 + 7*n^4 + 4*n^3 - 7*n^2 - 6*n)*a(n + 4) = 0, a(0) = 1, a(1) = 4, a(2) = 8, a(3) = 14, a(4) = 16, a(5) = 26}. - N. J. A. Sloane, Mar 28 2018
Equivalent conjecture: 9*a(n) = 40*n -18*(-1)^n -6*(-1)^n*A076118(n+1) +6*A049347(n) -4*A049347(n-1). - R. J. Mathar, Apr 01 2018

Extensions

More terms from Rémy Sigrist, Mar 28 2018

A301676 Coordination sequence for node of type V2 in "krs" 2-D tiling (or net).

Original entry on oeis.org

1, 4, 8, 13, 18, 22, 27, 31, 35, 41, 44, 48, 55, 57, 61, 69, 70, 74, 83, 83, 87, 97, 96, 100, 111, 109, 113, 125, 122, 126, 139, 135, 139, 153, 148, 152, 167, 161, 165, 181, 174, 178, 195, 187, 191, 209, 200, 204, 223, 213, 217, 237, 226, 230, 251, 239, 243
Offset: 0

Views

Author

N. J. A. Sloane, Mar 25 2018

Keywords

Comments

Linear recurrence and g.f. confirmed by Shutov/Maleev link. - Ray Chandler, Aug 31 2023

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. See Table 2.2.1, page 67, bottom row, 2nd tiling.

Crossrefs

Cf. A301674.
Coordination sequences for the 20 2-uniform tilings in the order in which they appear in the Galebach catalog, together with their names in the RCSR database (two sequences per tiling): #1 krt A265035, A265036; #2 cph A301287, A301289; #3 krm A301291, A301293; #4 krl A301298, A298024; #5 krq A301299, A301301; #6 krs A301674, A301676; #7 krr A301670, A301672; #8 krk A301291, A301293; #9 krn A301678, A301680; #10 krg A301682, A301684; #11 bew A008574, A296910; #12 krh A301686, A301688; #13 krf A301690, A301692; #14 krd A301694, A219529; #15 krc A301708, A301710; #16 usm A301712, A301714; #17 krj A219529, A301697; #18 kre A301716, A301718; #19 krb A301720, A301722; #20 kra A301724, A301726.

Programs

  • Mathematica
    LinearRecurrence[{0,0,2,0,0,-1},{1,4,8,13,18,22,27,31,35},100] (* Paolo Xausa, Nov 15 2023 *)
  • PARI
    \\ See Links section.

Formula

(a) G.f. = -(x^8+x^7-2*x^6-6*x^5-10*x^4-11*x^3-8*x^2-4*x-1)/(x^6-2*x^3+1). (b) Satisfies the recurrence {(-n^5+6*n^4-7*n^3-21*n^2+53*n-30)*a(n)+(3*n^3-24*n^2+51*n-30)*a(n+1)+(6*n^3-33*n^2+57*n-30)*a(n+2)+(n^5-9*n^4+25*n^3-12*n^2-35*n+30)*a(n+3) = 0, a(0) = 1, a(1) = 4, a(2) = 8, a(3) = 13, a(4) = 18, a(5) = 22}. - N. J. A. Sloane, Mar 28 2018

Extensions

More terms from Rémy Sigrist, Mar 28 2018

A301678 Coordination sequence for node of type V1 in "krn" 2-D tiling (or net).

Original entry on oeis.org

1, 5, 10, 14, 20, 26, 31, 36, 41, 46, 52, 58, 60, 65, 74, 79, 80, 86, 96, 98, 99, 108, 117, 118, 120, 130, 136, 137, 142, 151, 156, 158, 164, 170, 175, 180, 185, 190, 196, 202, 204, 209, 218, 223, 224, 230, 240, 242, 243, 252, 261, 262, 264, 274, 280, 281, 286, 295, 300, 302, 308, 314, 319, 324, 329
Offset: 0

Views

Author

N. J. A. Sloane, Mar 25 2018

Keywords

Comments

Linear recurrence and g.f. confirmed by Shutov/Maleev link. - Ray Chandler, Aug 30 2023

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. See Table 2.2.1, page 67, 3rd row, 2nd tiling.

Crossrefs

Cf. A301680.
Coordination sequences for the 20 2-uniform tilings in the order in which they appear in the Galebach catalog, together with their names in the RCSR database (two sequences per tiling): #1 krt A265035, A265036; #2 cph A301287, A301289; #3 krm A301291, A301293; #4 krl A301298, A298024; #5 krq A301299, A301301; #6 krs A301674, A301676; #7 krr A301670, A301672; #8 krk A301291, A301293; #9 krn A301678, A301680; #10 krg A301682, A301684; #11 bew A008574, A296910; #12 krh A301686, A301688; #13 krf A301690, A301692; #14 krd A301694, A219529; #15 krc A301708, A301710; #16 usm A301712, A301714; #17 krj A219529, A301697; #18 kre A301716, A301718; #19 krb A301720, A301722; #20 kra A301724, A301726.

Programs

  • Mathematica
    LinearRecurrence[{1,-1,1,0,0,0,1,-1,1,-1},{1,5,10,14,20,26,31,36,41,46,52,58,60},100] (* Paolo Xausa, Nov 15 2023 *)

Formula

G.f.: -(2*x^12-3*x^10-4*x^9-6*x^8-10*x^7-11*x^6-10*x^5-11*x^4-8*x^3-6*x^2-4*x-1)/(x^10-x^9+x^8-x^7-x^3+x^2-x+1). - N. J. A. Sloane, Mar 29 2018

Extensions

a(11)-a(100) from Davide M. Proserpio, Mar 28 2018

A301680 Coordination sequence for node of type V2 in "krn" 2-D tiling (or net).

Original entry on oeis.org

1, 4, 9, 15, 20, 26, 32, 36, 40, 46, 52, 56, 62, 68, 72, 76, 82, 88, 92, 98, 104, 108, 112, 118, 124, 128, 134, 140, 144, 148, 154, 160, 164, 170, 176, 180, 184, 190, 196, 200, 206, 212, 216, 220, 226, 232, 236, 242, 248, 252, 256, 262, 268, 272, 278, 284, 288, 292, 298, 304, 308, 314, 320, 324, 328
Offset: 0

Views

Author

N. J. A. Sloane, Mar 25 2018

Keywords

Comments

Linear recurrence and g.f. confirmed by Shutov/Maleev link. - Ray Chandler, Aug 30 2023

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. See Table 2.2.1, page 67, 3rd row, 2nd tiling.

Crossrefs

Cf. A301678.
Coordination sequences for the 20 2-uniform tilings in the order in which they appear in the Galebach catalog, together with their names in the RCSR database (two sequences per tiling): #1 krt A265035, A265036; #2 cph A301287, A301289; #3 krm A301291, A301293; #4 krl A301298, A298024; #5 krq A301299, A301301; #6 krs A301674, A301676; #7 krr A301670, A301672; #8 krk A301291, A301293; #9 krn A301678, A301680; #10 krg A301682, A301684; #11 bew A008574, A296910; #12 krh A301686, A301688; #13 krf A301690, A301692; #14 krd A301694, A219529; #15 krc A301708, A301710; #16 usm A301712, A301714; #17 krj A219529, A301697; #18 kre A301716, A301718; #19 krb A301720, A301722; #20 kra A301724, A301726.

Programs

  • Mathematica
    LinearRecurrence[{1,0,0,0,0,0,1,-1},{1,4,9,15,20,26,32,36,40,46,52,56},100] (* Paolo Xausa, Nov 15 2023 *)

Formula

G.f.: -(x^11-x^9-x^8-3*x^7-6*x^6-6*x^5-5*x^4-6*x^3-5*x^2-3*x-1)/(x^8-x^7-x+1). - N. J. A. Sloane, Mar 29 2018
Equivalent conjecture: 7*a(n) = 36*n-2*b(n) for n>3, where b(n>=1) = 4, 1, -2, 2, -1, -4, 0 (continued 7-periodic). - R. J. Mathar, Mar 30 2018

Extensions

a(11)-a(100) from Davide M. Proserpio, Mar 28 2018

A301682 Coordination sequence for node of type V1 in "krg" 2-D tiling (or net).

Original entry on oeis.org

1, 6, 6, 18, 18, 18, 36, 30, 30, 54, 42, 42, 72, 54, 54, 90, 66, 66, 108, 78, 78, 126, 90, 90, 144, 102, 102, 162, 114, 114, 180, 126, 126, 198, 138, 138, 216, 150, 150, 234, 162, 162, 252, 174, 174, 270, 186, 186, 288, 198, 198, 306, 210, 210, 324, 222, 222, 342, 234, 234, 360, 246, 246, 378, 258
Offset: 0

Views

Author

N. J. A. Sloane, Mar 25 2018

Keywords

Comments

Linear recurrence and g.f. confirmed by Shutov/Maleev link. - Ray Chandler, Aug 30 2023

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. See Table 2.2.1, page 66, 2nd row, 2nd tiling.

Crossrefs

Cf. A301684.
Coordination sequences for the 20 2-uniform tilings in the order in which they appear in the Galebach catalog, together with their names in the RCSR database (two sequences per tiling): #1 krt A265035, A265036; #2 cph A301287, A301289; #3 krm A301291, A301293; #4 krl A301298, A298024; #5 krq A301299, A301301; #6 krs A301674, A301676; #7 krr A301670, A301672; #8 krk A301291, A301293; #9 krn A301678, A301680; #10 krg A301682, A301684; #11 bew A008574, A296910; #12 krh A301686, A301688; #13 krf A301690, A301692; #14 krd A301694, A219529; #15 krc A301708, A301710; #16 usm A301712, A301714; #17 krj A219529, A301697; #18 kre A301716, A301718; #19 krb A301720, A301722; #20 kra A301724, A301726.

Programs

  • Mathematica
    LinearRecurrence[{0,0,2,0,0,-1},{1,6,6,18,18,18,36},100] (* Paolo Xausa, Nov 15 2023 *)

Formula

G.f.: -(-x^6-6*x^5-6*x^4-16*x^3-6*x^2-6*x-1)/(x^6-2*x^3+1). - N. J. A. Sloane, Mar 29 2018
a(n) = 2*(7*n + n*A099837(n+3) + 3*A049347(n+2))/3 for n > 0. - Stefano Spezia, Jun 08 2024

Extensions

a(11)-a(100) from Davide M. Proserpio, Mar 28 2018
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