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.

User: Cesar Bautista

Cesar Bautista's wiki page.

Cesar Bautista has authored 11 sequences. Here are the ten most recent ones:

A182141 Number of independent sets of nodes in the armchair (3,3) carbon nanotorus graph of breadth n (n>=1).

Original entry on oeis.org

27, 18, 322, 2787, 37730, 486773, 6616216, 89809934, 1226678898, 16759965210, 229174768672, 3134027776854, 42863602781324, 586250943722267, 8018366958787066, 109670557564651352, 1500014136347328018, 20516391520781511387, 280612359537735848734
Offset: 0

Author

Cesar Bautista, Apr 14 2012

Keywords

Programs

  • Maxima
    a[0]:27; a[1]:18; a[2]:322; a[3]:2787; a[4]:37730; a[5]:486773; a[6]:6616216; a[7]:89809934; a[8]:1226678898; a[9]:16759965210; a[10]:229174768672; a[11]:3134027776854; a[12]:42863602781324; a[13]:586250943722267; a[14]:8018366958787066; a[15]:109670557564651352; a[16]:1500014136347328018; a[17]:20516391520781511387; a[18]:280612359537735848734;
    a[n]:=18*a[n-1]-a[n-2]-1018*a[n-3]+1836*a[n-4]+20616*a[n-5]-43461*a[n-6]-185682*a[n-7]+384405*a[n-8]+762090*a[n-9]-1499721*a[n-10]-1538730*a[n-11]+2873116*a[n-12]+1499424*a[n-13]-2714609*a[n-14]-574862*a[n-15]+1107300*a[n-16]+18144*a[n-17]-108864*a[n-18];
    makelist(a[k],k,0,25);

Formula

a(n) = 18*a(n-1) -a(n-2) -1018*a(n-3) +1836*a(n-4) +20616*a(n-5) -43461*a(n-6) -185682*a(n-7) +384405*a(n-8) +762090*a(n-9) -1499721*a(n-10) -1538730*a(n-11) +2873116*a(n-12) +1499424*a(n-13) -2714609*a(n-14) -574862*a(n-15) +1107300*a(n-16) +18144*a(n-17) -108864*a(n-18).
G.f.: (979776*x^18 -75600*x^17 -12197940*x^16 +5916552*x^15 +35833019*x^14 -19220271*x^13 -44070216*x^12 +23310438*x^11 +26177559*x^10 -13274349*x^9 -7520073*x^8 +3654387*x^7 +940365*x^6 -451464*x^5 -43362*x^4 +24495*x^3 +25*x^2 -468*x+27)/( (x-1) *(x+1) *(3*x^3-5*x^2-5*x+1) *(36*x^4-x^3-20*x^2-x+1) *(36*x^4+x^3-20*x^2+x+1) *(28*x^5+42*x^4-109*x^3+17*x^2+13*x-1)).

A182130 Number of independent sets of nodes in the armchair (3,3) carbon nanotube graph of breadth n (n>=1).

Original entry on oeis.org

27, 322, 4556, 61814, 847098, 11580788, 158413552, 2166639646, 29634348798, 405322443028, 5543789598764, 75825036741014, 1037095063081722, 14184841682767868, 194012817135153904, 2653605447140034790, 36294622054374551742, 496418784252960527212
Offset: 0

Author

Cesar Bautista, Apr 13 2012

Keywords

Programs

  • Mathematica
    LinearRecurrence[{13, 17, -109, 42, 28}, {27, 322, 4556, 61814,
    847098}, 20] (* Wesley Ivan Hurt, Oct 10 2021 *)
  • Maxima
    a[0]:27; a[1]:322; a[2]:4556; a[3]:61814; a[4]:847098;
    a[n]:=13*a[n-1]+17*a[n-2]-109*a[n-3]+42*a[n-4]+28*a[n-5];
    makelist(a[k],k,0,25);

Formula

a(n) = 13*a(n-1)+17*a(n-2)-109*a(n-3)+42*a(n-4)+28*a(n-5) with a(0)=27, a(1)=322, a(2)=4556, a(3)=61814, a(4)=847098.
G.f.: (27-29*x-89*x^2+55*x^3+28*x^4)/(1-13*x-17*x^2+109*x^3-42*x^4-28*x^5).

A182143 Number of independent vertex sets in the Moebius ladder graph with 2n nodes (n >= 0).

Original entry on oeis.org

1, 3, 5, 15, 33, 83, 197, 479, 1153, 2787, 6725, 16239, 39201, 94643, 228485, 551615, 1331713, 3215043, 7761797, 18738639, 45239073, 109216787, 263672645, 636562079, 1536796801, 3710155683, 8957108165, 21624372015, 52205852193, 126036076403, 304278004997
Offset: 0

Author

Cesar Bautista, Apr 14 2012

Keywords

Comments

Also the number of vertex covers. - Eric W. Weisstein, Jan 04 2014

Crossrefs

Programs

  • Magma
    I:=[1,3,5]; [n le 3 select I[n] else Self(n-1)+3*Self(n-2)+Self(n-3): n in [1..31]]; // Bruno Berselli, Apr 14 2012
  • Mathematica
    Table[(1 + Sqrt[2])^n + (1 - Sqrt[2])^n - (-1)^n, {n, 0, 30}] (* Bruno Berselli, Apr 14 2012 *)
    Table[LucasL[n, 2] - (-1)^n, {n, 0, 20}] (* Vladimir Reshetnikov, Sep 15 2016 *)
    LinearRecurrence[{1, 3, 1}, {1, 3, 5}, 20] (* Eric W. Weisstein, Mar 31 2017 *)
    CoefficientList[Series[(-1 - 2 x + x^2)/(-1 + x + 3 x^2 + x^3), {x, 0, 20}], x] (* Eric W. Weisstein, Sep 21 2017 *)
  • PARI
    Vec((x^2-2*x-1)/((x+1)*(x^2+2*x-1))+O(x^31)) \\ Bruno Berselli, Apr 14 2012
    

Formula

G.f.: (x^2-2*x-1)/((x+1)*(x^2+2*x-1)).
a(n) = (1+sqrt(2))^n + (1-sqrt(2))^n - (-1)^n = A002203(n) - (-1)^n.
a(n) = a(n-1) + 3*a(n-2) + a(n-3) with a(0)=1, a(1)=3, a(2)=5.
From Peter Bala, Jun 29 2015: (Start)
a(n) = Pell(n-1) + Pell(n+1) - (-1)^n.
a(n) = [x^n] ( (1 + 2*x + sqrt(1 + 8*x + 8*x^2))/2 )^n.
exp( Sum_{n >= 1} a(n)*x^n/n ) = 1 + x + 3*x^2 + 7*x^3 + 17*x^4 + 41*x^5 + ... = Sum_{n >= 0} A001333*x^n. Cf. A098600. (End)

A182077 Number of independent sets of nodes in the generalized Petersen graph G(2n+1,2) (n>=1).

Original entry on oeis.org

13, 76, 435, 2461, 13971, 79197, 449188, 2547179, 14445169, 81917079, 464547653, 2634418076, 14939621779, 84721638085, 480451043995, 2724607324221, 15451075136020, 87622065595371, 496899168779481, 2817883624638175, 15980039054921477, 90621786488479756
Offset: 0

Author

Cesar Bautista, Apr 10 2012

Keywords

Programs

  • Mathematica
    LinearRecurrence[{3,15,3,-13,4},{13,76,435,2461,13971},30] (* Harvey P. Dale, Jul 22 2013 *)

Formula

a(n) = 3*a(n-1)+15*a(n-2)+3*a(n-3)-13*a(n-4)+4*a(n-5) with a(0)=13,a(1)=76,a(2)=435,a(3)=2461,a(4)=13971.
G.f.: (-4*x^4+23*x^3-12*x^2-37*x-13)/(4*x^5-13*x^4+3*x^3+15*x^2+3*x-1).

A182054 Number of independent sets of nodes in the generalized Petersen graph G(2n,2) (n>=0).

Original entry on oeis.org

8, 3, 39, 171, 1055, 5828, 33327, 188499, 1069855, 6065487, 34399844, 195074223, 1106262671, 6273528979, 35576813647, 201753798116, 1144133068159, 6488305791115, 36794770328583, 208660804936031, 1183302172416580, 6710431459264095, 38054430587741959
Offset: 0

Author

Cesar Bautista, Apr 08 2012

Keywords

Crossrefs

Cf. A182077.

Formula

a(n) = 3*a(n-1)+15*a(n-2)+3*a(n-3)-13*a(n-4)+4*a(n-5) with a(0)=8, a(1)=3, a(2)=39, a(3)=171, a(4)=1055, a(5)=5828.
G.f.: ((6*x^2-11*x-8)*(2*x^3-5*x^2-4*x+1)) / (4*x^5-13*x^4+3*x^3+15*x^2+3*x-1).

A182052 Number of independent sets of nodes in C_6 X C_n (n >= 1).

Original entry on oeis.org

18, 1, 199, 1300, 18995, 199821, 2406862, 27285777, 317960739, 3658040968, 42338077399, 488631332773, 5646974285234, 65218753680549, 753462136109959, 8703368091760320, 100541026090416195, 1161408360176875825, 13416320242101088558, 154981059170079355117
Offset: 0

Author

Cesar Bautista, Apr 08 2012

Keywords

References

  • M. Golin, Y. C. Leung, Y. J. Wang and X. R. Yong, Counting structures in grid-graphs, cylinders and tori using transfer matrices: Survey and new results. In: C. Demetrescu, R. Sedgewick and R.Tamassia, (eds.) The Proceedings of the Second Workshop on Analytic Algorithmics and Combinatorics (ANALCO05), SIAM, Philadelphia, (2005), 250-258.

Programs

  • Mathematica
    LinearRecurrence[{4,84,89,-575,-360,1301,115,-1032,295,119,-36,-4,1},{18,1,199,1300,18995,199821,2406862,27285777,317960739,3658040968,42338077399,488631332773,5646974285234},20](* Harvey P. Dale, Nov 24 2012 *)

Formula

a(n) = 4*a(n-1) +84*a(n-2) +89*a(n-3) -575*a(n-4) -360*a(n-5) +1301*a(n-6) +115*a(n-7) -1032*a(n-8) +295*a(n-9) +119*a(n-10) -36*a(n-11) -4*a(n-12) +a(n-13) with a(0)=18, a(1)=1, a(2)=199, a(3)=1300, a(4)=18995, a(5)=199821, a(6)=2406862, a(7)=27285777, a(8)=317960739, a(9)=3658040968, a(10)=42338077399, a(11)=488631332773, a(12)=5646974285234.
G.f: (-9*x^12 -67*x^11 +556*x^10 +1162*x^9 -6841*x^8 +1421*x^7 +12335*x^6 -3985*x^5 -7340*x^4 +1182*x^3 +1317*x^2 +71*x-18) / ((x-1) *(x^2-3*x-1) *(x^2-x-1) *(x^3+3*x^2-5*x-1) *(x^5-2*x^4-25*x^3-3*x^2+12*x-1)).

A182041 Number of independent sets of nodes in C_5 X C_n (n >= 1).

Original entry on oeis.org

11, 1, 81, 391, 3561, 25531, 199821, 1511931, 11589281, 88389661, 675443291, 5157630831, 39394699881, 300868345701, 2297915763861, 17550293888221, 134040955378561, 1023739686467981, 7818833928607761, 59716490127924211, 456085875187977011, 3483364700645591901
Offset: 0

Author

Cesar Bautista, Apr 07 2012

Keywords

References

  • M. Golin, Y. C. Leung, Y. J. Wang and X. R. Yong, Counting structures in grid-graphs, cylinders and tori using transfer matrices: Survey and new results. In: Demetrescu, C., Sedgewick, R., Tamassia, R., (eds.) The Proceedings of the Second Workshop on Analytic Algorithmics and Combinatorics (ANALCO05), SIAM, Philadelphia, (2005), 250-258.

Programs

  • Mathematica
    LinearRecurrence[{4,27,10,-30,-7,8,-1},{11,1,81,391,3561,25531,199821},30] (* Harvey P. Dale, Mar 06 2013 *)

Formula

a(n)=4*a(n-1)+27*a(n-2)+10*a(n-3)-30*a(n-4)-7*a(n-5)+8*a(n-6)-a(n-7) with a(0)=11, a(1)=1, a[2]=81, a(3)=391, a(4)=3561, a(5)=25531, a(6)=199821.
G.f.: (-11*x^6+27*x^5+130*x^4-70*x^3-220*x^2-43*x+11)/((x^3-5*x^2-7*x+1)*(x^4-3*x^3-x^2+3*x+1)).

A182019 Number of independent sets of nodes in graph C_8 x P_n (n>=0).

Original entry on oeis.org

1, 47, 1155, 30277, 788453, 20546803, 535404487, 13951571713, 363549830913, 9473376491295, 246857112567171, 6432599206076589, 167620580643483109, 4367854759124964451, 113817498564834289095, 2965854794621630365713, 77284202988962060229833
Offset: 0

Author

Cesar Bautista, Apr 06 2012

Keywords

Crossrefs

Row 8 of A286513.

Formula

a(n) = 29*a(n-1)-65*a(n-2)-317*a(n-3)+334*a(n-4)+187*a(n-5)-109*a(n-6)+5*a(n-7)+a(n-8) with a(0)=1, a(1)=47,a(2)=1155,a(3)=30277,a(4)=788453, a(5)=20546803, a(6)=535404487, a(7)=13951571713.
G.f.: -(x^7 +4*x^6 -79*x^5 +60*x^4 +154*x^3 -143*x^2 +18*x +1)/(x^8 +5*x^7 -109*x^6 +187*x^5 +334*x^4 -317*x^3 -65*x^2 +29*x -1). [Colin Barker, Aug 31 2012]

A182014 Number of independent sets of nodes in graph C_7 x P_n (n>=0).

Original entry on oeis.org

1, 29, 477, 8303, 143697, 2488431, 43089985, 746156517, 12920616493, 223736359029, 3874270087045, 67087749098875, 1161706844818941, 20116382073294655, 348339884131004417, 6031933298656980345, 104450339960964929961, 1808686034441106749965
Offset: 0

Author

Cesar Bautista, Apr 06 2012

Keywords

Crossrefs

Row 7 of A286513.

Programs

  • Mathematica
    LinearRecurrence[{17,8,-44,5,1},{1,29,477,8303,143697},30] (* Harvey P. Dale, Aug 27 2012 *)
  • PARI
    Vec((x^4+6*x^3-24*x^2+12*x+1)/(-x^5-5*x^4+44*x^3-8*x^2-17*x+1)+O(x^99)) \\ Charles R Greathouse IV, Apr 06 2012

Formula

a(n) = 17*a(n-1) + 8*a(n-2) - 44*a(n-3) + 5*a(n-4) + a(n-5) with a(0)=1, a(1)=29, a(2)=477, a(3)=8303, a(4)=143697.
G.f.: (x^4+6*x^3-24*x^2+12*x+1)/(-x^5-5*x^4+44*x^3-8*x^2-17*x+1).

A181989 Number of independent sets of nodes in graph C_5 x P_n (n >= 0).

Original entry on oeis.org

1, 11, 81, 621, 4741, 36211, 276561, 2112241, 16132281, 123210611, 941023441, 7187084861, 54891500621, 419234905211, 3201914754721, 24454686308481, 186773143027761, 1426483517982011, 10894795654704401, 83209214029813101, 635511992964231701, 4853735225243983011
Offset: 0

Author

Cesar Bautista, Apr 04 2012

Keywords

Crossrefs

Row 5 of A286513.

Formula

a(n) = 7*a(n-1) + 5*a(n-2) - a(n-3) with a(0)=1, a(1)=11, a(2)=81.
G.f.: (1+4*x-x^2)/(x^3-5*x^2-7*x+1).