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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A008389 Coordination sequence for A_7 lattice.

Original entry on oeis.org

1, 56, 812, 5768, 26474, 91112, 256508, 623576, 1356194, 2703512, 5025692, 8823080, 14768810, 23744840, 36881420, 55599992, 81659522, 117206264, 164826956, 227605448, 309182762, 413820584, 546468188, 712832792, 919453346
Offset: 0

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Author

Keywords

Crossrefs

Row 7 of A103881.

Programs

  • Magma
    [1] cat [2 +n^2*(143*n^4 +770*n^2 +707)/30: n in [1..40]]; // G. C. Greubel, May 26 2023
    
  • Maple
    1, seq(2 +n^2*(143*n^4 +770*n^2 +707)/30, n=1..50);
  • Mathematica
    Table[n^2*(143*n^4 +770*n^2 +707)/30 +2 -Boole[n==0], {n,0,40}] (* G. C. Greubel, May 26 2023 *)
  • SageMath
    [2 +n^2*(143*n^4 +770*n^2 +707)/30 -int(n==0) for n in range(41)] # G. C. Greubel, May 26 2023

Formula

G.f.: (1+x)*(1+48*x+393*x^2+832*x^3+393*x^4+48*x^5+x^6)/(1-x)^7. - Colin Barker, Sep 26 2012
a(n) = 2 + n^2*(143*n^4 +770*n^2 +707)/30 with n>0, a(0)=1. - Bruno Berselli, Sep 26 2012
E.g.f.: -1 + (1/30)*(60 +1620*x +10530*x^2 +17490*x^3 +10065*x^4 +2145*x^5 +143*x^6)*exp(x). - G. C. Greubel, May 26 2023

A008399 Coordination sequence for E_6 lattice.

Original entry on oeis.org

1, 72, 1062, 6696, 26316, 77688, 189810, 405720, 785304, 1408104, 2376126, 3816648, 5885028, 8767512, 12684042, 17891064, 24684336, 33401736, 44426070, 58187880, 75168252, 95901624, 120978594, 151048728, 186823368, 229078440, 278657262, 336473352, 403513236
Offset: 0

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Author

Keywords

References

  • M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908.

Crossrefs

Programs

  • Magma
    [1] cat [9*n*(13*n^2+7)*(n^2+1)/5: n in [1..40]]; // G. C. Greubel, May 29 2023
    
  • Maple
    1, seq(117/5*n^5+36*n^3+63/5*n, n=1..30);
  • Mathematica
    LinearRecurrence[{6,-15,20,-15,6,-1},{1,72,1062,6696,26316,77688, 189810},30] (* Harvey P. Dale, Oct 24 2022 *)
  • SageMath
    [9*n*(13*n^2+7)*(n^2+1)//5 +int(n==0) for n in range(41)] # G. C. Greubel, May 29 2023

Formula

a(n) = 9*n*(13*n^2+7)*(n^2+1)/5 for n >= 1.
Bacher et al. give a g.f.
G.f.: (1+66*x+645*x^2+1384*x^3+645*x^4+66*x^5+x^6)/(1-x)^6 = 1 + 18*x*(4+35*x+78*x^2+35*x^3+4*x^4)/(1-x)^6. - Colin Barker, Sep 26 2012
E.g.f.: 1 + (1/5)*x*(360 + 2295*x + 3105*x^2 + 1170*x^3 + 117*x^4 )*exp(x). - G. C. Greubel, May 29 2023

A008401 Coordination sequence for {E_6}* lattice.

Original entry on oeis.org

1, 54, 828, 5202, 20376, 60030, 146484, 312858, 605232, 1084806, 1830060, 2938914, 4530888, 6749262, 9763236, 13770090, 18997344, 25704918, 34187292, 44775666, 57840120, 73791774, 93084948
Offset: 0

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Author

Keywords

References

  • M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908.

Crossrefs

Cf. A008402 (partial sums).

Programs

  • Magma
    [1] cat [6*n*(3*n^4+5*n^2+1): n in [1..40]]; // G. C. Greubel, May 30 2023
    
  • Mathematica
    Join[{1},Table[18 n^5+30 n^3+6 n,{n,30}]] (* Harvey P. Dale, May 16 2012 *)
  • SageMath
    [6*n*(3*n^4+5*n^2+1) +int(n==0) for n in range(41)] # G. C. Greubel, May 30 2023

Formula

a(n) = 6*n*(3*n^4 + 5*n^2 + 1), n > 0.
G.f.: (1+48*x+519*x^2+1024*x^3+519*x^4+48*x^5+x^6)/(1-x)^6.
E.g.f.: 1 + 6*exp(x)*x*(9 + 60*x + 80*x^2 + 30*x^3 + 3*x^4). - Stefano Spezia, Apr 15 2022

A008402 Crystal ball sequence for {E_6}* lattice.

Original entry on oeis.org

1, 55, 883, 6085, 26461, 86491, 232975, 545833, 1151065, 2235871, 4065931, 7004845, 11535733, 18284995, 28048231, 41818321, 60815665, 86520583, 120707875, 165483541, 223323661, 297115435
Offset: 0

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Author

Keywords

References

  • M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908.

Crossrefs

Partial sums of A008401.

Programs

  • Magma
    [1 +3*n*(n+1)*(n^2+n+1)^2: n in [0..40]]; // G. C. Greubel, May 31 2023
    
  • Mathematica
    CoefficientList[Series[(1+48x+519x^2+1024x^3+519x^4+48x^5+x^6)/(1-x)^7,{x,0,30}],x] (* or *) LinearRecurrence[{7,-21,35,-35,21,-7,1},{1,55, 883,6085,26461,86491,232975},30] (* Harvey P. Dale, Jun 20 2013 *)
  • PARI
    3*n^6+9*n^5+15*n^4+15*n^3+9*n^2+3*n+1 \\ Charles R Greathouse IV, Jun 20 2013
    
  • SageMath
    [1 +3*n*(n+1)*(n^2+n+1)^2 for n in range(41)] # G. C. Greubel, May 31 2023

Formula

G.f.: (1 + 48*x + 519*x^2 + 1024*x^3 + 519*x^4 + 48*x^5 + x^6)/(1-x)^7.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7); a(0)=1, a(1)=55, a(2)=883, a(3)=6085, a(4)=26461, a(5)=86491, a(6)=232975. - Harvey P. Dale, Jun 20 2013
a(n) = 3*n^6 + 9*n^5 + 15*n^4 + 15*n^3 + 9*n^2 + 3*n + 1 = 1 + 3*n*(n+1)*(n^2+n+1)^2. - Charles R Greathouse IV, Jun 20 2013
E.g.f.: exp(x)*(1 + 54*x + 387*x^2 + 600*x^3 + 300*x^4 + 54*x^5 + 3*x^6). - Stefano Spezia, Apr 15 2022

A008530 Coordination sequence for 4-dimensional primitive di-isohexagonal orthogonal lattice.

Original entry on oeis.org

1, 12, 60, 180, 408, 780, 1332, 2100, 3120, 4428, 6060, 8052, 10440, 13260, 16548, 20340, 24672, 29580, 35100, 41268, 48120, 55692, 64020, 73140, 83088, 93900, 105612, 118260, 131880, 146508, 162180, 178932, 196800, 215820, 236028, 257460, 280152, 304140, 329460, 356148, 384240
Offset: 0

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Comments

Coordination sequence for 4-dimensional cyclotomic lattice Z[zeta_12].

Examples

			3*a(5) = 2340 = (2*5+1)^3 + (2*5-1)^3 + (5+1)^3 + (5-1)^3. - _Bruno Berselli_, Jan 31 2013
		

References

  • M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908.

Programs

  • GAP
    Concatenation([1], List([1..45], n-> 6*n*(1+n^2) )); # G. C. Greubel, Nov 10 2019
  • Magma
    [1]cat[6*n^3+6*n: n in [1..45]]; // Vincenzo Librandi, Apr 16 2012
    
  • Maple
    1, seq( 6*k^3+6*k, k=1..45);
  • Mathematica
    CoefficientList[Series[(1+4*x+x^2)^2/(1-x)^4,{x,0,45}],x] (* Vincenzo Librandi, Apr 16 2012 *)
    LinearRecurrence[{4,-6,4,-1}, {1,12,60,180,408}, 45] (* G. C. Greubel, Nov 10 2019 *)
  • PARI
    vector(46, n, if(n==1,1, 6*(n-1)*(1+(n-1)^2)) ) \\ G. C. Greubel, Nov 10 2019
    
  • Sage
    [1]+[6*n*(1+n^2) for n in (1..45)] # G. C. Greubel, Nov 10 2019
    

Formula

G.f.: (1+4*x+x^2)^2/(1-x)^4. - Colin Barker, Apr 14 2012
3*a(n) = (2*n+1)^3 + (2*n-1)^3 + (n+1)^3 + (n-1)^3 for n>0. - Bruno Berselli, Jan 31 2013
E.g.f.: 1 + x*(12 + 18*x + 6*x^2)*exp(x). - G. C. Greubel, Nov 10 2019

A008534 Coordination sequence for {A_6}* lattice.

Original entry on oeis.org

1, 14, 98, 462, 1596, 4410, 10374, 21658, 41272, 73206, 122570, 195734, 300468, 446082, 643566, 905730, 1247344, 1685278, 2238642, 2928926, 3780140, 4818954, 6074838, 7580202, 9370536, 11484550, 13964314, 16855398, 20207012, 24072146, 28507710, 33574674, 39338208, 45867822
Offset: 0

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Comments

Equally, coordination sequence for 6-dimensional cyclotomic lattice Z[zeta_14].

References

  • M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908.

Programs

  • GAP
    Concatenation([1], List([1..45], n-> 7*n*(6+5*n^2+n^4)/6 )); # G. C. Greubel, Nov 10 2019
  • Magma
    [1] cat [7*n*(6+5*n^2+n^4)/6: n in [1..45]]; // G. C. Greubel, Nov 10 2019
    
  • Maple
    1, seq( (7*k^5+35*k^3+42*k)/6, k=1..40);
  • Mathematica
    CoefficientList[Series[(x^6 +8x^5 +29x^4 +64x^3 +29x^2 +8x +1)/(x-1)^6, {x, 0, 50}], x] (* Vincenzo Librandi, Jun 20 2013 *)
    Table[If[n==0,1, 7*n*(6+5*n^2+n^4)/6], {n,0,40}] (* G. C. Greubel, Nov 10 2019 *)
  • PARI
    vector(46, n, if(n==1,1, 7*(n-1)*(6+5*(n-1)^2+(n-1)^4)/6 ) ) \\ G. C. Greubel, Nov 10 2019
    
  • Sage
    [1]+[7*n*(6+5*n^2+n^4)/6 for n in (1..45)]; # G. C. Greubel, Nov 10 2019
    

Formula

G.f.: (x^6+8*x^5+29*x^4+64*x^3+29*x^2+8*x+1)/(x-1)^6. [Conway-Sloane] - Colin Barker, Sep 21 2012
a(n) = (7/6)*n*(n^2+2)*(n^2+3) for n>0, a(0)=1. - Bruno Berselli, Feb 28 2013
E.g.f.: 1 + x*(84 + 210*x + 210*x^2 + 70*x^3 + 7*x^4)*exp(x)/6. - G. C. Greubel, Nov 10 2019

A008400 Crystal ball sequence for E_6 lattice.

Original entry on oeis.org

1, 73, 1135, 7831, 34147, 111835, 301645, 707365, 1492669, 2900773, 5276899, 9093547, 14978575, 23746087, 36430129, 54321193, 79005529, 112407265, 156833335, 215021215, 290189467, 386091091
Offset: 0

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Author

Keywords

References

  • M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908.

Programs

  • Magma
    [1 +3*n*(n+1)*(26*n^4 +52*n^3 +73*n^2 +47*n +42)/20: n in [0..40]]; // G. C. Greubel, May 30 2023
    
  • Maple
    seq(39/10*n^6+117/10*n^5+75/4*n^4+18*n^3+267/20*n^2+63/10*n+1, n=0..35);
  • Mathematica
    Table[39/10 n^6+117/10 n^5+75/4 n^4+18n^3+267/20 n^2+63/10 n+1, {n,0, 30}] (* or *) LinearRecurrence[{7,-21,35,-35,21,-7,1},{1,73,1135, 7831,34147,111835,301645},30] (* Harvey P. Dale, Feb 23 2015 *)
  • PARI
    a(n)=(78*n^6 + 234*n^5 + 375*n^4 + 360*n^3 + 267*n^2 + 126*n + 20)/20 \\ Charles R Greathouse IV, Feb 10 2017
    
  • SageMath
    [1 +3*n*(n+1)*(26*n^4 +52*n^3 +73*n^2 +47*n +42)//20 for n in range(41)] # G. C. Greubel, May 30 2023

Formula

a(n) = 1 + (3/20)*n*(n+1)*(26*n^4 + 52*n^3 + 73*n^2 + 47*n + 42).
G.f.: (1+66*x+645*x^2+1384*x^3+645*x^4+66*x^5+x^6)/(1-x)^7. - Colin Barker, Mar 16 2012
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7). - Harvey P. Dale, Feb 23 2015
E.g.f.: (1/20)*(20 + 1440*x + 9900*x^2 + 15480*x^3 + 7785*x^4 + 1404*x^5 + 78*x^6)*exp(x). - G. C. Greubel, May 30 2023

A008529 Coordination sequence for 4-dimensional face-centered cubic orthogonal lattice.

Original entry on oeis.org

1, 14, 68, 202, 456, 870, 1484, 2338, 3472, 4926, 6740, 8954, 11608, 14742, 18396, 22610, 27424, 32878, 39012, 45866, 53480, 61894, 71148, 81282, 92336, 104350, 117364, 131418, 146552, 162806, 180220, 198834, 218688, 239822, 262276, 286090, 311304, 337958, 366092, 395746, 426960
Offset: 0

Views

Author

Keywords

References

  • M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908.

Programs

  • GAP
    Concatenation([1], List([1..45], n-> 2*n*(11 +10*n^2)/3 )); # G. C. Greubel, Nov 09 2019
  • Magma
    [1] cat [(20*n^3+22*n)/3: n in [1..45]]; // Vincenzo Librandi, Apr 16 2012
    
  • Maple
    1, seq( (20*k^3+22*k)/3, k=1..45);
  • Mathematica
    CoefficientList[Series[(1+x)^2*(1+8*x+x^2)/(1-x)^4,{x,0,45}],x] (* Vincenzo Librandi, Apr 16 2012 *)
    Table[If[n==0,1, 2*n*(11 +10*n^2)/3], {n,0,45}] (* or *) LinearRecurrence[{4,-6,4,-1}, {1,14,68,202,456}, 46] (* G. C. Greubel, Nov 09 2019 *)
  • PARI
    vector(46, n, if(n==1,1, 2*(n-1)*(11 +10*(n-1)^2)/3) ) \\ G. C. Greubel, Nov 09 2019
    
  • Sage
    [1]+[2*n*(11 +10*n^2)/3 for n in (1..45)]; # G. C. Greubel, Nov 09 2019
    

Formula

G.f.: (1+x)^2*(1+8*x+x^2)/(1-x)^4. - Colin Barker, Apr 14 2012
E.g.f.: 1 + (42 + 60*x^2 + 20*x^3)*exp(x)/3. - G. C. Greubel, Nov 09 2019

A008532 Coordination sequence for 4-dimensional I-centered cubic orthogonal lattice.

Original entry on oeis.org

1, 10, 44, 126, 280, 530, 900, 1414, 2096, 2970, 4060, 5390, 6984, 8866, 11060, 13590, 16480, 19754, 23436, 27550, 32120, 37170, 42724, 48806, 55440, 62650, 70460, 78894, 87976, 97730, 108180, 119350, 131264, 143946, 157420, 171710, 186840, 202834, 219716, 237510
Offset: 0

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Comments

Let f(x) = x^2 + x + 1 then sequence gives f(f(n+1)) - f(f(n)), n >= 0.

Programs

  • GAP
    Concatenation([1], List([1..45], n-> 2*n*(3+2*n^2) )); # G. C. Greubel, Nov 10 2019
  • Magma
    [1] cat [2*n*(3+2*n^2): n in [1..45]]; // G. C. Greubel, Nov 10 2019
    
  • Maple
    1, seq( 4*k^3+6*k, k=1..40);
  • Mathematica
    Table[If[n==0,1,2*n*(3+2*n^2)], {n,0,40}] (* G. C. Greubel, Nov 10 2019 *)
  • PARI
    Vec((x+1)^2*(x^2+4*x+1)/(x-1)^4 + O(x^40)) \\ Colin Barker, Mar 03 2015
    
  • PARI
    vector(46, n, if(n==1,1, 2*(n-1)*(3 +2*(n-1)^2) ) ) \\ G. C. Greubel, Nov 10 2019
    
  • Sage
    [1]+[2*n*(3+2*n^2) for n in (1..45)]; # G. C. Greubel, Nov 10 2019
    

Formula

a(n) = 4*n^3 + 6*n, n >= 1.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>4. - Colin Barker, Mar 03 2015
G.f.: (1+x)^2*(1+4*x+x^2)/(1-x)^4. - Colin Barker, Mar 03 2015
a(0) = 1; for n > 0, a(n) = A005898(n-1) + A005898(n) = (n-1)^3 + 2n^3 + (n+1)^3. - Doug Bell, Aug 18 2015
E.g.f.: 1 + 2*x*(5 + 6*x + 2*x^2)*exp(x). - G. C. Greubel, Aug 21 2015

A008533 Coordination sequence for {A_5}* lattice.

Original entry on oeis.org

1, 12, 72, 272, 762, 1752, 3512, 6372, 10722, 17012, 25752, 37512, 52922, 72672, 97512, 128252, 165762, 210972, 264872, 328512, 403002, 489512, 589272, 703572, 833762, 981252, 1147512, 1334072, 1542522, 1774512, 2031752, 2316012, 2629122, 2972972, 3349512
Offset: 0

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Author

Keywords

Programs

  • GAP
    Concatenation([1], List([1..45], n-> (4+15*n^2+5*n^4)/2 )); # G. C. Greubel, Nov 10 2019
  • Magma
    [1] cat [(4+15*n^2+5*n^4)/2: n in [1..45]]; // G. C. Greubel, Nov 10 2019
    
  • Maple
    1, seq( (5*k^4+15*k^2+4)/2, k=1..40);
  • Mathematica
    Table[If[n==0, 1, (4+15*n^2+5*n^4)/2], {n,0,40}] (* G. C. Greubel, Nov 10 2019 *)
    LinearRecurrence[{5,-10,10,-5,1},{1,12,72,272,762,1752},50] (* Harvey P. Dale, Jan 08 2020 *)
  • PARI
    Vec(-(x+1)*(x^4+6*x^3+16*x^2+6*x+1) / (x-1)^5 + O(x^40)) \\ Colin Barker, Mar 03 2015
    
  • PARI
    vector(46, n, if(n==1,1, (4 +15*(n-1)^2 +5*(n-1)^4)/2 ) ) \\ G. C. Greubel, Nov 10 2019
    
  • Sage
    [1]+[(4+15*n^2+5*n^4)/2 for n in (1..45)]; # G. C. Greubel, Nov 10 2019
    

Formula

a(n) = 5*a(n-1) -10*a(n-2) +10*a(n-3) -5*a(n-4) +a(n-5) for n>5. - Colin Barker, Mar 03 2015
G.f.: (1+x)*(1+6*x+16*x^2+6*x^3+x^4)/(1-x)^5. - Colin Barker, Mar 03 2015
E.g.f.: -1 + (4 + 20*x + 50*x^2 + 30*x^3 + 5*x^4)*exp(x)/2. - G. C. Greubel, Nov 10 2019
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