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 25 results. Next

A045846 Number of distinct ways to cut an n X n square into squares with integer sides.

Original entry on oeis.org

1, 1, 2, 6, 40, 472, 10668, 450924, 35863972, 5353011036, 1500957422222, 790347882174804, 781621363452405930, 1451740730942350766748, 5064070747064013556294032, 33176273260130056822126522884, 408199838581532754602910469192704
Offset: 0

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Author

Keywords

Examples

			For n=3 the 6 dissections are: the full 3 X 3 square; 9 1 X 1 squares; one 2 X 2 square and five 1 X 1 squares (in 4 ways).
		

Crossrefs

Diagonal of A219924. - Alois P. Heinz, Dec 01 2012
See A224239 for the number of inequivalent ways.

Programs

  • Maple
    b:= proc(n, l) option remember; local i, k, s, t;
          if max(l[])>n then 0 elif n=0 or l=[] then 1
        elif min(l[])>0 then t:=min(l[]); b(n-t, map(h->h-t, l))
        else for k do if l[k]=0 then break fi od; s:=0;
             for i from k to nops(l) while l[i]=0 do s:=s+
               b(n, [l[j]$j=1..k-1, 1+i-k$j=k..i, l[j]$j=i+1..nops(l)])
             od; s
          fi
        end:
    a:= n-> b(n, [0$n]):
    seq(a(n), n=0..11);  # Alois P. Heinz, Apr 15 2013
  • Mathematica
    $RecursionLimit = 1000; b[n_, l_List] := b[n, l] = Module[{i, k, s, t}, Which[ Max[l]>n, 0, n == 0 || l == {}, 1, Min[l]>0, t = Min[l]; b[n-t, l-t], True, For[k = 1, True, k++, If[l[[k]] == 0, Break[]]]; s=0; For[i=k, i <= Length[l] && l[[i]] == 0, i++, s = s + b[n, Join[l[[1 ;; k-1]], Table[1+i-k, {i-k+1}], l[[i+1 ;; Length[l]]]]]]; s]]; a[n_] := b[n, Array[0&, n]]; Table[a[n], {n, 0, 11}] (* Jean-François Alcover, Feb 25 2015, after Alois P. Heinz *)

Formula

It appears lim n->oo a(n)*a(n-3)/(a(n-1)*a(n-2)) = 3.527... - Gerald McGarvey, May 03 2005
It appears that lim n->oo a(n)*a(n-2)/(a(n-1))^2 = 1.8781... - Christopher Hunt Gribble, Jun 21 2013
a(n) = (1/n^2) * Sum_{k=1..n} k^2 * A226936(n,k). - Alois P. Heinz, Jun 22 2013

Extensions

More terms from Hugo van der Sanden, Nov 06 2000
a(14)-a(15) from Alois P. Heinz, Nov 30 2012
a(16) from Steve Butler, Mar 14 2014

A224239 Number of inequivalent ways to cut an n X n square into squares with integer sides.

Original entry on oeis.org

1, 2, 3, 13, 77, 1494, 56978, 4495023, 669203528, 187623057932, 98793520541768, 97702673827558670
Offset: 1

Views

Author

N. J. A. Sloane, Apr 15 2013

Keywords

Comments

Similar to A045846, but now we do not regard dissections which differ by a rotation and/or reflection as distinct.

Examples

			For n=5, the illustrations (see links) show that the 77 solutions consist of:
4 dissections each with 1 image under the group of the square, for a total of 4,
2 dissections each with 2 images under the group of the square, totaling 4,
26 dissections each with 4 images under the group of the square, totaling 104, and
45 dissections each with 8 images under the group of the square, totaling 360,
for a grand total of 77 dissections with 472 images, agreeing with A045846(5) = 472.
		

Crossrefs

Main diagonal of A227690.

Extensions

a(6)-a(10) from Don Reble, Apr 15 2013
a(11)-a(12) from Ed Wynn, 2013. - N. J. A. Sloane, Nov 29 2013

A113881 Table of smallest number of squares, T(m,n), needed to tile an m X n rectangle, read by antidiagonals.

Original entry on oeis.org

1, 2, 2, 3, 1, 3, 4, 3, 3, 4, 5, 2, 1, 2, 5, 6, 4, 4, 4, 4, 6, 7, 3, 4, 1, 4, 3, 7, 8, 5, 2, 5, 5, 2, 5, 8, 9, 4, 5, 3, 1, 3, 5, 4, 9, 10, 6, 5, 5, 5, 5, 5, 5, 6, 10, 11, 5, 3, 2, 5, 1, 5, 2, 3, 5, 11, 12, 7, 6, 6, 5, 5, 5, 5, 6, 6, 7, 12, 13, 6, 6, 4, 6, 4, 1, 4, 6, 4, 6, 6, 13, 14, 8, 4, 6, 2, 3, 7, 7, 3, 2, 6, 4, 8, 14
Offset: 1

Views

Author

Devin Kilminster (devin(AT)27720.net), Jan 27 2006

Keywords

Comments

a(n) = A338573(n) for n <= 105, as stated by R. J. Mathar. These sequences are essentially different though, because a(13433) = T(67,98) = T(98,67) = a(13464), but A338573(13433) != A338573(13464). The relationship between the tiling problem and resistor networks is remarkable. There are explanations in M. Ortolano et al., 2013. - Rainer Rosenthal, Nov 09 2020

Examples

			T(n,n) = 1 (1 n X n square).
T(n,1) = n (n 1 X 1 squares).
T(6,7) = 6 (2 3 X 3, 1 4 X 4, 1 2 X 2, 2 1 X 1).
T(11,13) = 6 (1 7 X 7, 1 6 X 6, 1 5 X 5, 2 4 X 4 1 1 X 1).
Table T(m,n) begins:
:   1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ...
:   2, 1, 3, 2, 4, 3, 5, 4, 6,  5, ...
:   3, 3, 1, 4, 4, 2, 5, 5, 3,  6, ...
:   4, 2, 4, 1, 5, 3, 5, 2, 6,  4, ...
:   5, 4, 4, 5, 1, 5, 5, 5, 6,  2, ...
:   6, 3, 2, 3, 5, 1, 5, 4, 3,  4, ...
:   7, 5, 5, 5, 5, 5, 1, 7, 6,  6, ...
:   8, 4, 5, 2, 5, 4, 7, 1, 7,  5, ...
:   9, 6, 3, 6, 6, 3, 6, 7, 1,  6, ...
:  10, 5, 6, 4, 2, 4, 6, 5, 6,  1, ...
		

Crossrefs

Programs

  • Mathematica
    (* *** Warning *** This empirical toy-program is based on the greedy algorithm. Its output was only verified for n+k <= 32. Any use outside this domain might produce only upper bounds instead of minimums. *)
    nmax = 31; Clear[T];
    Tmin[n_, k_] := Table[{1 + T[ c, k - c] + T[n - c, k], 1 + T[n, k - c] + T[n - c, c]}, {c, 1, k - 1}] // Flatten // Min;
    Tmin2[n_, k_] := Module[{n1, n2, k1, k2}, 1 + T[n2, k1 + 1] + T[n - n1, k2] + T[n - n2, k1] + T[n1, k - k1] /. {Reduce[1 <= n1 <= n - 1 && 1 <= n2 <= n - 1 && 1 <= k1 <= k - 1 && 1 <= k2 <= k - 1 && n1 + 1 + n2 == n && k1 + 1 + k2 == k, Integers] // ToRules} // Min];
    T[n_, n_] = 1;
    T[n_, 1] := n;
    T[1, k_] := k;
    T[n_, k_ /; k > 1] /; n > k && Divisible[n, k] := n/k;
    T[n_, k_ /; k > 1] /; n > k := T[n, k] = If[k >= 5 && n >= 6 && n - k <= 3, Min[Tmin[n, k], Tmin2[n, k], T[k, n - k] + 1], T[k, n - k] + 1];
    T[n_, k_ /; k > 1] /; n < k := T[n, k] = T[k, n];
    Table[T[n - k + 1, k], {n, 1, nmax}, {k, 1, n}] // Flatten (* Jean-François Alcover, Mar 11 2016, checked against first 496 terms of the b-file *)

A054856 Number of ways to tile a 4 X n region with 1 X 1, 2 X 2, 3 X 3 and 4 X 4 tiles.

Original entry on oeis.org

1, 1, 5, 13, 40, 117, 348, 1029, 3049, 9028, 26738, 79183, 234502, 694476, 2056692, 6090891, 18038173, 53420041, 158203433, 468519406, 1387520047, 4109140098, 12169216863, 36039131181, 106729873498, 316080480394, 936072224321
Offset: 0

Views

Author

Silvia Heubach (silvi(AT)cine.net), Apr 21 2000

Keywords

Comments

It is easy to see that the g.f. for indecomposable tilings, i.e. those that cannot be split vertically into smaller tilings, is g=z+4*z^2+2*z^3+z^4+2*z^3/(1-z); then G.f.=1/(1-g). - Emeric Deutsch, Oct 16 2006

Examples

			a(2)=5 as there is one tiling of a 4 X 2 region with only 1 X 1 tiles, 3 tilings with exactly one 2 X 2 tile and 1 tiling with exactly two 2 X 2 tiles.
		

Crossrefs

Column k=4 of A219924. - Alois P. Heinz, Dec 01 2012

Programs

  • Maple
    a[0]:=1: a[1]:=1: a[2]:=5: a[3]:=13: a[4]:=40: for n from 5 to 26 do a[n]:=2*a[n-1]+3*a[n-2]-a[n-4]-a[n-5] od: seq(a[n],n=0..26); # Emeric Deutsch, Oct 16 2006
  • Mathematica
    f[ A_ ] := Module[ {til = A, sum}, sum = 2* Apply[ Plus, Drop[ til, -4 ] ]; AppendTo[ til, A[ [ -1 ] ] + 4A[ [ -2 ] ] + 4A[ [ -3 ] ] + 3A[ [ -4 ] ] + sum ] ]; NumOfTilings[ n_ ] := Nest[ f, {1, 1, 5, 13}, n - 2 ]; NumOfTilings[ 30 ]

Formula

a(n) = a(n-1)+4*a(n-2)+4*a(n-3)+3*a(n-4)+2*( a(n-5)+a(n-6)+...+a(0)), a(0)=a(1)=1, a(2)=5, a(3)=13
a(n) = 2*a(n-1)+3*a(n-2)-a(n-4)-a(n-5). G.f.=(1-z)/((1+z)*(1-3*z+z^4)). - Emeric Deutsch, Oct 16 2006

A227690 Number A(n,k) of tilings of a k X n rectangle using integer-sided square tiles reduced for symmetry; square array A(n,k), n >= 0, k >= 0, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 4, 3, 4, 1, 1, 1, 1, 5, 6, 6, 5, 1, 1, 1, 1, 9, 10, 13, 10, 9, 1, 1, 1, 1, 12, 21, 39, 39, 21, 12, 1, 1, 1, 1, 21, 39, 115, 77, 115, 39, 21, 1, 1, 1, 1, 30, 82, 295, 521, 521, 295, 82, 30, 1, 1
Offset: 0

Views

Author

Keywords

Examples

			Square array A(n,k) begins:
  1, 1,  1,  1,   1,    1,     1,      1,       1, ...
  1, 1,  1,  1,   1,    1,     1,      1,       1, ...
  1, 1,  2,  2,   4,    5,     9,     12,      21, ...
  1, 1,  2,  3,   6,   10,    21,     39,      82, ...
  1, 1,  4,  6,  13,   39,   115,    295,     861, ...
  1, 1,  5, 10,  39,   77,   521,   1985,    8038, ...
  1, 1,  9, 21, 115,  521,  1494,  15129,   83609, ...
  1, 1, 12, 39, 295, 1985, 15129,  56978,  861159, ...
  1, 1, 21, 82, 861, 8038, 83609, 861159, 4495023, ...
...
A(4,3) = 6 because there are 6 ways to tile a 3 X 4 rectangle by subsquares, reduced for symmetry, i.e., where rotations and reflections are not counted as distinct:
   ._____ _.    ._______.    ._______.
   |     |_|    |   |   |    |   |_|_|
   |     |_|    |___|_ _|    |___|   |
   |_____|_|    |_|_|_|_|    |_|_|___|
   ._______.    ._______.    ._______.
   |   |_|_|    |_|   |_|    |_|_|_|_|
   |___|_|_|    |_|___|_|    |_|_|_|_|
   |_|_|_|_|    |_|_|_|_|    |_|_|_|_|
		

Crossrefs

A054857 Number of ways to tile a 5 X n region with square tiles of size up to 5 X 5.

Original entry on oeis.org

1, 1, 8, 28, 117, 472, 1916, 7765, 31497, 127707, 517881, 2100025, 8515772, 34532063, 140030059, 567832091, 2302600696, 9337214060, 37863085664, 153537580071, 622606110920, 2524713292359, 10237896957896, 41515420557135
Offset: 0

Views

Author

Silvia Heubach (silvi(AT)cine.net), Apr 21 2000

Keywords

Examples

			a(2) = 8 as there is 1 tiling of a 5 X 2 region with only 1 X 1 tiles, 4 tilings with exactly one 2 X 2 tile and 3 tilings with exactly two 2 X 2 tiles.
		

Crossrefs

Column k=5 of A219924. - Alois P. Heinz, Dec 01 2012

Programs

  • Mathematica
    f[ {A_, B_} ] := Module[ {til = A, basic = B}, {Flatten[ Append[ til, ListConvolve[ A, B ] ] ], AppendTo[ basic, B[ [ -1 ] ] + B[ [ -2 ] ] + B[ [ -3 ] ] ]} ]; NumOfTilings[ n_ ] := Nest[ f, {{1, 1, 8, 28, 117, 472, 1916, 7765}, {1, 7, 13, 20, 35, 66, 118, 218}}, n - 2 ][ [ 1 ] ] NumOfTilings[ 30 ]

Formula

a(n) = b(1)a(n-1)+b(2)a(n-2)+...+b(n)a(0), a(0)=a(1)=1, b(n) as defined in A054858.
a(n) = 2*a(n-1) +7*a(n-2) +6*a(n-3) -a(n-4) -5*a(n-5) -2*a(n-6) -3*a(n-7) -a(n-8). - R. J. Mathar, Nov 02 2008
G.f.: -(x^3+x^2+x-1)/(x^8+3*x^7+2*x^6+5*x^5+x^4-6*x^3-7*x^2-2*x+1). - Colin Barker, Jul 10 2012

A226545 Number A(n,k) of squares in all tilings of a k X n rectangle using integer-sided square tiles; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

0, 0, 0, 0, 1, 0, 0, 2, 2, 0, 0, 3, 5, 3, 0, 0, 4, 12, 12, 4, 0, 0, 5, 25, 34, 25, 5, 0, 0, 6, 50, 98, 98, 50, 6, 0, 0, 7, 96, 256, 386, 256, 96, 7, 0, 0, 8, 180, 654, 1402, 1402, 654, 180, 8, 0, 0, 9, 331, 1625, 4938, 6940, 4938, 1625, 331, 9, 0
Offset: 0

Views

Author

Alois P. Heinz, Jun 10 2013

Keywords

Examples

			A(3,3) = 1 + 6 + 6 + 6 + 6 + 9 = 34:
  ._____.  ._____.  ._____.  ._____.  ._____.  ._____.
  |     |  |   |_|  |_|   |  |_|_|_|  |_|_|_|  |_|_|_|
  |     |  |___|_|  |_|___|  |_|   |  |   |_|  |_|_|_|
  |_____|  |_|_|_|  |_|_|_|  |_|___|  |___|_|  |_|_|_|
Square array A(n,k) begins:
  0, 0,   0,    0,     0,      0,       0,        0, ...
  0, 1,   2,    3,     4,      5,       6,        7, ...
  0, 2,   5,   12,    25,     50,      96,      180, ...
  0, 3,  12,   34,    98,    256,     654,     1625, ...
  0, 4,  25,   98,   386,   1402,    4938,    16936, ...
  0, 5,  50,  256,  1402,   6940,   33502,   157279, ...
  0, 6,  96,  654,  4938,  33502,  221672,  1426734, ...
  0, 7, 180, 1625, 16936, 157279, 1426734, 12582472, ...
		

Crossrefs

Columns (or rows) k=0-10 give: A000004, A001477, A067331(n-1) for n>0, A226546, A226547, A226548, A226549, A226550, A226551, A226552, A226553.
Main diagonal gives A226554.

Programs

  • Maple
    b:= proc(n, l) option remember; local i, k, s, t;
          if max(l[])>n then [0,0] elif n=0 or l=[] then [1,0]
        elif min(l[])>0 then t:=min(l[]); b(n-t, map(h->h-t, l))
        else for k do if l[k]=0 then break fi od; s:=[0$2];
             for i from k to nops(l) while l[i]=0 do s:=s+(h->h+[0, h[1]])
               (b(n, [l[j]$j=1..k-1, 1+i-k$j=k..i, l[j]$j=i+1..nops(l)]))
             od; s
          fi
        end:
    A:= (n, k)-> `if`(n>=k, b(n, [0$k]), b(k, [0$n]))[2]:
    seq(seq(A(n, d-n), n=0..d), d=0..14);
  • Mathematica
    b[n_, l_List] := b[n, l] = Module[{i, k, s, t}, Which[Max[l] > n, {0, 0}, n == 0 || l == {}, {1, 0}, Min[l] > 0, t=Min[l]; b[n-t, l-t], True, k = Position[l, 0, 1][[1, 1]]; s={0, 0}; For[i=k, i <= Length[l] && l[[i]] == 0, i++, s = s + Function[h, h+{0, h[[1]]}][b[n, Join[l[[1 ;; k-1]], Table[1+i-k, {j, k, i}], l[[i+1 ;; -1]]]]] ]; s]]; a[n_, k_] := If[n >= k, b[n, Array[0&, k]], b[k, Array[0&, n]]][[2]]; Table[Table[a[n, d-n], {n, 0, d}], {d, 0, 14}] // Flatten (* Jean-François Alcover, Dec 13 2013, translated from Maple *)

A219925 Number of tilings of a 6 X n rectangle using integer-sided square tiles.

Original entry on oeis.org

1, 1, 13, 60, 348, 1916, 10668, 59257, 329350, 1830234, 10171315, 56525022, 314128014, 1745708992, 9701463927, 53914132251, 299618062228, 1665073290365, 9253344266757, 51423790446062, 285778433090830, 1588162056821687, 8825923956549044, 49048479247236561
Offset: 0

Views

Author

Alois P. Heinz, Dec 01 2012

Keywords

Examples

			a(2) = 13, because there are 13 tilings of a 6 X 2 rectangle using integer-sided square tiles:
._._.  .___.  ._._.  ._._.  ._._.  ._._.
|_|_|  |   |  |_|_|  |_|_|  |_|_|  |_|_|
|_|_|  |___|  |   |  |_|_|  |_|_|  |_|_|
|_|_|  |_|_|  |___|  |   |  |_|_|  |_|_|
|_|_|  |_|_|  |_|_|  |___|  |   |  |_|_|
|_|_|  |_|_|  |_|_|  |_|_|  |___|  |   |
|_|_|  |_|_|  |_|_|  |_|_|  |_|_|  |___|
.___.  .___.  .___.  ._._.  ._._.  ._._.  .___.
|   |  |   |  |   |  |_|_|  |_|_|  |_|_|  |   |
|___|  |___|  |___|  |   |  |   |  |_|_|  |___|
|   |  |_|_|  |_|_|  |___|  |___|  |   |  |   |
|___|  |   |  |_|_|  |   |  |_|_|  |___|  |___|
|_|_|  |___|  |   |  |___|  |   |  |   |  |   |
|_|_|  |_|_|  |___|  |_|_|  |___|  |___|  |___|
		

Crossrefs

Column k=6 of A219924.
Cf. A226549.

Programs

  • Maple
    gf:= -(2*x^9 +3*x^8 +2*x^7 -3*x^6 -7*x^5 -4*x^4 -3*x^3 +5*x^2 +2*x -1) / (2*x^15 +7*x^14 +12*x^13 +6*x^12 -18*x^11 -13*x^10 -8*x^9 -27*x^8 -32*x^7 +x^6 +40*x^5 +34*x^4 -3*x^3 -15*x^2 -3*x +1):
    a:= n-> coeff (series (gf, x, n+1), x, n):
    seq (a(n), n=0..40);

Formula

G.f.: see Maple program.

A219926 Number of tilings of a 7 X n rectangle using integer-sided square tiles.

Original entry on oeis.org

1, 1, 21, 129, 1029, 7765, 59257, 450924, 3435392, 26160354, 199243634, 1517411733, 11556549312, 88013947545, 670309228276, 5105035683160, 38879655193542, 296105186372225, 2255119850966932, 17174861374796123, 130802743517191075, 996186073044886758
Offset: 0

Views

Author

Alois P. Heinz, Dec 01 2012

Keywords

Examples

			a(2) = 21, because there are 21 tilings of a 7 X 2 rectangle using integer-sided square tiles:
._._. .___. ._._. ._._. ._._. ._._. ._._. .___. .___. .___. .___.
|_|_| |   | |_|_| |_|_| |_|_| |_|_| |_|_| |   | |   | |   | |   |
|_|_| |___| |   | |_|_| |_|_| |_|_| |_|_| |___| |___| |___| |___|
|_|_| |_|_| |___| |   | |_|_| |_|_| |_|_| |   | |_|_| |_|_| |_|_|
|_|_| |_|_| |_|_| |___| |   | |_|_| |_|_| |___| |   | |_|_| |_|_|
|_|_| |_|_| |_|_| |_|_| |___| |   | |_|_| |_|_| |___| |   | |_|_|
|_|_| |_|_| |_|_| |_|_| |_|_| |___| |   | |_|_| |_|_| |___| |   |
|_|_| |_|_| |_|_| |_|_| |_|_| |_|_| |___| |_|_| |_|_| |_|_| |___|
._._. ._._. ._._. ._._. ._._. ._._. .___. .___. .___. ._._.
|_|_| |_|_| |_|_| |_|_| |_|_| |_|_| |   | |   | |   | |_|_|
|   | |   | |   | |_|_| |_|_| |_|_| |___| |___| |___| |   |
|___| |___| |___| |   | |   | |_|_| |   | |   | |_|_| |___|
|   | |_|_| |_|_| |___| |___| |   | |___| |___| |   | |   |
|___| |   | |_|_| |   | |_|_| |___| |   | |_|_| |___| |___|
|_|_| |___| |   | |___| |   | |   | |___| |   | |   | |   |
|_|_| |_|_| |___| |_|_| |___| |___| |_|_| |___| |___| |___|
		

Crossrefs

Column k=7 of A219924.
Cf. A226550.

Programs

  • Maple
    gf:= -(6*x^18 -x^17 -9*x^16 +13*x^15 +20*x^14 -35*x^13 -47*x^12 -76*x^11 -145*x^10 -127*x^9 -8*x^8 +64*x^7 +96*x^6 +68*x^5 +7*x^4 -10*x^3 -13*x^2 -2*x +1) / (6*x^25 +11*x^24 -9*x^23 -10*x^22 +39*x^21 +12*x^20 -70*x^19 -281*x^18 -403*x^17 -110*x^16 -118*x^15 -790*x^14 -179*x^13 +466*x^12 +327*x^11 +669*x^10 +1028*x^9 +231*x^8 -45*x^7 -284*x^6 -273*x^5 -61*x^4 +45*x^3 +31*x^2 +3*x -1):
    a:= n-> coeff(series(gf, x, n+1), x, n):
    seq(a(n), n=0..30);

Formula

G.f.: see Maple program.

A219927 Number of tilings of an 8 X n rectangle using integer-sided square tiles.

Original entry on oeis.org

1, 1, 34, 277, 3049, 31497, 329350, 3435392, 35863972, 374285478, 3906605183, 40773605243, 425562898029, 4441677458152, 46358636450427, 483853831650209, 5050074056261222, 52708577944998395, 550129399697072615, 5741804607960538038, 59928300863912394900
Offset: 0

Views

Author

Alois P. Heinz, Dec 01 2012

Keywords

Crossrefs

Column k=8 of A219924.
Cf. A226551.

Programs

  • Maple
    gf:= -(60*x^40 +136*x^39 -321*x^38 -1038*x^37 -2045*x^36 +2501*x^35 +4393*x^34 +7347*x^33 +4372*x^32 -4825*x^31 -13838*x^30 -19585*x^29 -9331*x^28 -40213*x^27 +19891*x^26 +57417*x^25 +68058*x^24 +10427*x^23 -8789*x^22 +6040*x^21 -76684*x^20 -81024*x^19 -16484*x^18 +11908*x^17 +42083*x^16 +63711*x^15 +19938*x^14 -2290*x^13 -18240*x^12 -18560*x^11 -7633*x^10 +291*x^9 +4194*x^8 +2502*x^7 +378*x^6 -361*x^5 -240*x^4 -33*x^3 +27*x^2 +5*x -1) /
    (60*x^48 +256*x^47 +35*x^46 -1488*x^45 -4435*x^44 -2543*x^43 +7032*x^42 +16610*x^41 +23043*x^40 +18924*x^39 +3186*x^38 -57091*x^37 -115830*x^36 -141242*x^35 +18849*x^34 +39846*x^33 +240064*x^32 +433164*x^31 +162501*x^30 -692061*x^29 -641988*x^28 +446013*x^27 +530385*x^26 +657974*x^25 -654746*x^24 -708014*x^23 -43614*x^22 -370550*x^21 +356235*x^20 +824516*x^19 +224413*x^18 -94736*x^17 -143852*x^16 -344353*x^15 -110166*x^14 +15107*x^13 +55317*x^12 +51581*x^11 +29259*x^10 +6818*x^9 -5977*x^8 -8807*x^7 -2453*x^6 +1175*x^5 +708*x^4 +15*x^3 -55*x^2 -6*x +1):
    a:= n-> coeff(series(gf, x, n+1), x, n):
    seq(a(n), n=0..30);

Formula

G.f.: see Maple program.
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