A006300
Number of rooted maps with n edges on torus.
Original entry on oeis.org
1, 20, 307, 4280, 56914, 736568, 9370183, 117822512, 1469283166, 18210135416, 224636864830, 2760899996816, 33833099832484, 413610917006000, 5046403030066927, 61468359153954656, 747672504476150374, 9083423595292949240, 110239596847544663002, 1336700736225591436496, 16195256987701502444284
Offset: 2
- E. R. Canfield, Calculating the number of rooted maps on a surface, Congr. Numerantium, 76 (1990), 21-34.
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
- T. R. S. Walsh, Combinatorial Enumeration of Non-Planar Maps. Ph.D. Dissertation, Univ. of Toronto, 1971.
- T. D. Noe, Table of n, a(n) for n = 2..100
- D. Arquès, Relations fonctionnelles et dénombrement des cartes pointées sur le tore, J. Combin. Theory Ser. B, 43 (1987), 253-274.
- E. A. Bender, E. R. Canfield and R. W. Robinson, The enumeration of maps on the torus and the projective plane, Canad. Math. Bull., 31 (1988), 257-271.
- Sean R. Carrell, Guillaume Chapuy, Simple recurrence formulas to count maps on orientable surfaces, arXiv:1402.6300 [math.CO], (19-March-2014).
- S. R. Finch, An exceptional convolutional recurrence, arXiv:2408.12440 [math.CO], 22 Aug 2024.
- A. D. Mednykh and R. Nedela, Enumeration of unrooted maps with given genus, preprint (submitted to J. Combin. Th. B).
- A. D. Mednykh and R. Nedela, Enumeration of unrooted maps with given genus, Discrete Mathematics, Volume 310, Issue 3, 6 February 2010, pp. 518-526.
- T. R. S. Walsh and A. B. Lehman, Counting rooted maps by genus, J. Comb. Thy B13 (1972), 122-141 and 192-218.
- T. R. S. Walsh, Counting maps on doughnuts, Theoretical Computer Science, vol. 502, pp. 4-15, (September-2013).
Rooted maps with n edges of genus g for 0 <= g <= 10:
A000168, this sequence,
A006301,
A104742,
A215402,
A238355,
A238356,
A238357,
A238358,
A238359,
A238360.
-
R:=sqrt(1-12*x): seq(coeff(convert(series((R-1)^2/(12*R^2*(R+2)),x,50),polynom),x,n),n=2..25); (Pab Ter)
-
Drop[With[{c=Sqrt[1-12x]},CoefficientList[Series[(c-1)^2/(12c^2 (c+2)), {x,0,30}],x]],2] (* Harvey P. Dale, Jun 14 2011 *)
-
A005159_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-12*x))/(6*x);
A006300_ser(N) = my(y = A005159_ser(N+1)); y*(y-1)^2/(3*(y-2)^2*(y+2));
Vec(A006300_ser(21)) \\ Gheorghe Coserea, Jun 02 2017
Bender et al. give 20 terms.
More terms from Pab Ter (pabrlos2(AT)yahoo.com), Nov 07 2005
A269919
Triangle read by rows: T(n,g) is the number of rooted maps with n edges on an orientable surface of genus g.
Original entry on oeis.org
1, 2, 9, 1, 54, 20, 378, 307, 21, 2916, 4280, 966, 24057, 56914, 27954, 1485, 208494, 736568, 650076, 113256, 1876446, 9370183, 13271982, 5008230, 225225, 17399772, 117822512, 248371380, 167808024, 24635754, 165297834, 1469283166, 4366441128
Offset: 0
Triangle starts:
n\g [0] [1] [2] [3] [4]
[0] 1;
[1] 2;
[2] 9, 1;
[3] 54, 20;
[4] 378, 307, 21;
[5] 2916, 4280, 966;
[6] 24057, 56914, 27954, 1485;
[7] 208494, 736568, 650076, 113256;
[8] 1876446, 9370183, 13271982, 5008230, 225225;
[9] 17399772, 117822512, 248371380, 167808024, 24635754;
[10] ...
Columns g=0-10 give:
A000168,
A006300,
A006301,
A104742,
A215402,
A238355,
A238356,
A238357,
A238358,
A238359,
A238360.
Same as
A238396 except for the zeros.
-
T[0, 0] = 1; T[n_, g_] /; g<0 || g>n/2 = 0; T[n_, g_] := T[n, g] = ((4n-2)/ 3 T[n-1, g] + (2n-3)(2n-2)(2n-1)/12 T[n-2, g-1] + 1/2 Sum[(2k-1)(2(n-k)- 1) T[k-1, i] T[n-k-1, g-i], {k, 1, n-1}, {i, 0, g}])/((n+1)/6);
Table[T[n, g], {n, 0, 10}, {g, 0, n/2}] // Flatten (* Jean-François Alcover, Jul 20 2018 *)
-
N = 9; gmax(n) = n\2;
Q = matrix(N+1, N+1);
Qget(n, g) = { if (g < 0 || g > n/2, 0, Q[n+1, g+1]) };
Qset(n, g, v) = { Q[n+1, g+1] = v };
Quadric({x=1}) = {
Qset(0, 0, x);
for (n = 1, N, for (g = 0, gmax(n),
my(t1 = (1+x)*(2*n-1)/3 * Qget(n-1, g),
t2 = (2*n-3)*(2*n-2)*(2*n-1)/12 * Qget(n-2, g-1),
t3 = 1/2 * sum(k = 1, n-1, sum(i = 0, g,
(2*k-1) * (2*(n-k)-1) * Qget(k-1, i) * Qget(n-k-1, g-i))));
Qset(n, g, (t1 + t2 + t3) * 6/(n+1))));
};
Quadric();
concat(vector(N+1, n, vector(1 + gmax(n-1), g, Qget(n-1, g-1))))
A006301
Number of rooted genus-2 maps with n edges.
Original entry on oeis.org
0, 0, 0, 0, 21, 966, 27954, 650076, 13271982, 248371380, 4366441128, 73231116024, 1183803697278, 18579191525700, 284601154513452, 4272100949982600, 63034617139799916, 916440476048146056, 13154166812674577412, 186700695099591735024, 2623742783421329300190, 36548087103760045010148, 505099724454854883618924
Offset: 0
- E. R. Canfield, Calculating the number of rooted maps on a surface, Congr. Numerantium, 76 (1990), 21-34.
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
- T. R. S. Walsh, Combinatorial Enumeration of Non-Planar Maps. Ph.D. Dissertation, Univ. of Toronto, 1971.
- T. D. Noe, Table of n, a(n) for n=0..30 (from Mednykh and Nedela)
- E. A. Bender and E. R. Canfield, The number of rooted maps on an orientable surface, J. Combin. Theory, B 53 (1991), 293-299.
- Sean R. Carrell, Guillaume Chapuy, Simple recurrence formulas to count maps on orientable surfaces, arXiv:1402.6300 [math.CO], (19-March-2014).
- S. R. Finch, An exceptional convolutional recurrence, arXiv:2408.12440 [math.CO], 22 Aug 2024.
- T. R. S. Walsh and A. B. Lehman, Counting rooted maps by genus, J. Comb. Thy B13 (1972), 122-141 and 192-218.
Rooted maps with n edges of genus g for 0 <= g <= 10:
A000168,
A006300, this sequence,
A104742,
A215402,
A238355,
A238356,
A238357,
A238358,
A238359,
A238360.
-
T[0, 0] = 1; T[n_, g_] /; g < 0 || g > n/2 = 0; T[n_, g_] := T[n, g] = ((4 n - 2)/3 T[n - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 T[n - 2, g - 1] + 1/2 Sum[(2 k - 1) (2 (n - k) - 1) T[k - 1, i] T[n - k - 1, g - i], {k, 1, n - 1}, {i, 0, g}])/((n + 1)/6);
a[n_] := T[n, 2];
Table[a[n], {n, 0, 30}] (* Jean-François Alcover, Jul 20 2018 *)
-
A005159_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-12*x))/(6*x);
A006301_ser(N) = {
my(y=A005159_ser(N+1));
-y*(y-1)^4*(4*y^4 - 16*y^3 + 153*y^2 - 148*y + 196)/(9*(y-2)^7*(y+2)^4);
};
concat([0,0,0,0], Vec(A006301_ser(19))) \\ Gheorghe Coserea, Jun 02 2017
A104742
Number of rooted maps of (orientable) genus 3 containing n edges.
Original entry on oeis.org
1485, 113256, 5008230, 167808024, 4721384790, 117593590752, 2675326679856, 56740864304592, 1137757854901806, 21789659909226960, 401602392805341924, 7165100439281414160, 124314235272290304540, 2105172926498512761984, 34899691847703927826500, 567797719808735191344672, 9084445205688065541367710
Offset: 6
- T. D. Noe, Table of n, a(n) for n = 6..30 (from Mednykh and Nedela)
- E. A. Bender and E. R. Canfield, The number of rooted maps on an orientable surface, J. Combin. Theory, B 53 (1991), 293-299.
- Sean R. Carrell, Guillaume Chapuy, Simple recurrence formulas to count maps on orientable surfaces, arXiv:1402.6300 [math.CO], (19-March-2014).
- S. R. Finch, An exceptional convolutional recurrence, arXiv:2408.12440 [math.CO], 22 Aug 2024.
- A. D. Mednykh and R. Nedela, Enumeration of unrooted maps with given genus, preprint (submitted to J. Combin. Th. B).
Rooted maps with n edges of genus g for 0 <= g <= 10:
A000168,
A006300,
A006301, this sequence,
A215402,
A238355,
A238356,
A238357,
A238358,
A238359,
A238360.
-
T[0, 0] = 1; T[n_, g_] /; g < 0 || g > n/2 = 0; T[n_, g_] := T[n, g] = ((4 n - 2)/3 T[n - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 T[n - 2, g - 1] + 1/2 Sum[(2 k - 1) (2 (n - k) - 1) T[k - 1, i] T[n - k - 1, g - i], {k, 1, n - 1}, {i, 0, g}])/((n + 1)/6);
a[n_] := T[n, 3];
Table[a[n], {n, 6, 30}] (* Jean-François Alcover, Jul 20 2018 *)
-
A005159_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-12*x))/(6*x);
A104742_ser(N) = {
my(y=A005159_ser(N+1));
y*(y-1)^6*(460*y^8 - 3680*y^7 + 63055*y^6 - 198110*y^5 + 835954*y^4 - 1408808*y^3 + 1986832*y^2 - 1462400*y + 547552)/(81*(y-2)^12*(y+2)^7)
};
Vec(A104742_ser(17)) \\ Gheorghe Coserea, Jun 02 2017
A238355
Number of rooted maps of genus 5 containing n edges.
Original entry on oeis.org
59520825, 8608033980, 672868675017, 37680386599440, 1692352190653740, 64755027944420400, 2190839204960030106, 67194704604610557072, 1901727022434216910002, 50322107898515282999256, 1257582616997225194094310, 29916524874047762719113408, 681758763997451748190036272, 14960113428664295584816860864
Offset: 10
Rooted maps with n edges of genus g for 0 <= g <= 10:
A000168,
A006300,
A006301,
A104742,
A215402, this sequence,
A238356,
A238357,
A238358,
A238359,
A238360.
-
T[0, 0] = 1; T[n_, g_] /; g < 0 || g > n/2 = 0; T[n_, g_] := T[n, g] = ((4 n - 2)/3 T[n - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 T[n - 2, g - 1] + 1/2 Sum[(2 k - 1) (2 (n - k) - 1) T[k - 1, i] T[n - k - 1, g - i], {k, 1, n - 1}, {i, 0, g}])/((n + 1)/6);
a[n_] := T[n, 5];
Table[a[n], {n, 10, 30}] (* Jean-François Alcover, Jul 20 2018 *)
-
\\ see A238396
-
A005159_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-12*x))/(6*x);
A238355_ser(N) = {
my(y=A005159_ser(N+1));
y*(y-1)^10*(3149956*y^16 - 50399296*y^15 + 1641189689*y^14 - 12178227918*y^13 + 118643174857*y^12 - 572499071300*y^11 + 2690451915197*y^10 - 8657342508522*y^9 + 23652302179098*y^8 - 49891059998872*y^7 + 84432024838000*y^6 - 112355956173344*y^5 + 115338024848256*y^4 - 88846084908160*y^3 + 48488699816960*y^2 - 16837415717888*y + 2841312026112)/(243*(y-2)^22*(y+2)^13);
};
Vec(A238355_ser(14)) \\ Gheorghe Coserea, Jun 02 2017
A238356
Number of rooted maps of genus 6 containing n edges.
Original entry on oeis.org
24325703325, 4416286056750, 425671555397220, 28948474436455224, 1558252224413413380, 70639804918689629112, 2802850363447807024080, 99911395098598706576856, 3259947795252652107008514, 98729808377337068918681196, 2805432194025270702468165744
Offset: 12
Rooted maps with n edges of genus g for 0 <= g <= 10:
A000168,
A006300,
A006301,
A104742,
A215402,
A238355, this sequence,
A238357,
A238358,
A238359,
A238360.
-
T[0, 0] = 1; T[n_, g_] /; g < 0 || g > n/2 = 0; T[n_, g_] := T[n, g] = ((4 n - 2)/3 T[n - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 T[n - 2, g - 1] + 1/2 Sum[(2 k - 1) (2 (n - k) - 1) T[k - 1, i] T[n - k - 1, g - i], {k, 1, n - 1}, {i, 0, g}])/((n + 1)/6);
a[n_] := T[n, 6];
Table[a[n], {n, 12, 30}] (* Jean-François Alcover, Jul 20 2018 *)
-
\\ see A238396
-
A005159_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-12*x))/(6*x);
A238356_ser(N) = {
my(y=A005159_ser(N+1));
-y*(y-1)^12*(3091382412*y^20 - 61827648240*y^19 + 2494741456179*y^18 - 23821030780564*y^17 + 297709107215018*y^16 - 1898397937026724*y^15 + 11996625283021532*y^14 - 53079600835119544*y^13 + 206468965657569764*y^12 - 637634273350412392*y^11 + 1660605297373850222*y^10 - 3573247507645221112*y^9 + 6390852378647917144*y^8 - 9449999309170921856*y^7 + 11435897504002339264*y^6 - 11175919884930946304*y^5 + 8621441033651120896*y^4 - 5068129528843341824*y^3 + 2141653827725309440*y^2 - 581932716954417152*y + 76958488611567616)/(2187*(y-2)^27*(y+2)^16);
};
Vec(A238356_ser(11)) \\ Gheorghe Coserea, Jun 02 2017
A238357
Number of genus-7 rooted maps with n edges.
Original entry on oeis.org
14230536445125, 3128879373858000, 360626952084151500, 29001816720933903504, 1828003659229082834100, 96187365300257285300064, 4395215998078319892167640, 179153431308203084149883760, 6641365771586560905099092466, 227189907562197156785567456832, 7252879937219595844346639732688
Offset: 14
Rooted maps with n edges of genus g for 0 <= g <= 10:
A000168,
A006300,
A006301,
A104742,
A215402,
A238355,
A238356, this sequence,
A238358,
A238359,
A238360.
-
T[0, 0] = 1; T[n_, g_] /; g < 0 || g > n/2 = 0; T[n_, g_] := T[n, g] = ((4 n - 2)/3 T[n - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 T[n - 2, g - 1] + 1/2 Sum[(2 k - 1) (2 (n - k) - 1) T[k - 1, i] T[n - k - 1, g - i], {k, 1, n - 1}, {i, 0, g}])/((n + 1)/6);
a[n_] := T[n, 7];
Table[a[n], {n, 14, 30}] (* Jean-François Alcover, Jul 20 2018 *)
-
\\ see A238396
-
system("wget http://oeis.org/A238357/a238357.txt");
A005159_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-12*x))/(6*x);
A238357_ser(N) = subst(read("a238357.txt"), 'y, A005159_ser(N+14));
Vec(A238357_ser(11)) \\ Gheorghe Coserea, Jun 03 2017
A238358
Number of genus-8 rooted maps with n edges.
Original entry on oeis.org
11288163762500625, 2927974178219879250, 394372363395179602125, 36751560969705187643982, 2663973075006196131775590, 160098273686603663417293308, 8303278159618015743881266599, 381958851175370643701603049354, 15896435050196091382215375181044, 607566907750822335161584110201960
Offset: 16
Rooted maps with n edges of genus g for 0 <= g <= 10:
A000168,
A006300,
A006301,
A104742,
A215402,
A238355,
A238356,
A238357, this sequence,
A238359,
A238360.
-
T[0, 0] = 1; T[n_, g_] /; g < 0 || g > n/2 = 0; T[n_, g_] := T[n, g] = ((4 n - 2)/3 T[n - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 T[n - 2, g - 1] + 1/2 Sum[(2 k - 1) (2 (n - k) - 1) T[k - 1, i] T[n - k - 1, g - i], {k, 1, n - 1}, {i, 0, g}])/((n + 1)/6);
a[n_] := T[n, 8];
Table[a[n], {n, 16, 30}] (* Jean-François Alcover, Jul 20 2018 *)
-
\\ see A238396
A238359
Number of genus-9 rooted maps with n edges.
Original entry on oeis.org
11665426077721040625, 3498878057690404966500, 540996834819906946713375, 57494374008560749302297480, 4724172886681078698955547790, 320061005837218582787265273000, 18618409220753939214291224549409, 956146512935178711199035220384800, 44232688287025023758415781081779828, 1871678026675570344184400604255444240
Offset: 18
Rooted maps with n edges of genus g for 0 <= g <= 10:
A000168,
A006300,
A006301,
A104742,
A215402,
A238355,
A238356,
A238357,
A238358, this sequence,
A238360.
-
T[0, 0] = 1; T[n_, g_] /; g < 0 || g > n/2 = 0; T[n_, g_] := T[n, g] = ((4 n - 2)/3 T[n - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 T[n - 2, g - 1] + 1/2 Sum[(2 k - 1) (2 (n - k) - 1) T[k - 1, i] T[n - k - 1, g - i], {k, 1, n - 1}, {i, 0, g}])/((n + 1)/6);
a[n_] := T[n, 9];
Table[a[n], {n, 18, 30}] (* Jean-François Alcover, Jul 20 2018 *)
-
\\ see A238396
A238360
Number of genus-10 rooted maps with n edges.
Original entry on oeis.org
15230046989184655753125, 5199629454143883380553750, 909887917857275652461097750, 108861830345440643086946970900, 10021124647635764856828690342402, 757187906770815991999545249667404, 48918614114003431712044170834572688, 2779227352989564224315657269511192976, 141720718575991991799057452443438430580
Offset: 20
Rooted maps with n edges of genus g for 0 <= g <= 10:
A000168,
A006300,
A006301,
A104742,
A215402,
A238355,
A238356,
A238357,
A238358,
A238359, this sequence.
-
T[0, 0] = 1; T[n_, g_] /; g < 0 || g > n/2 = 0; T[n_, g_] := T[n, g] = ((4 n - 2)/3 T[n - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 T[n - 2, g - 1] + 1/2 Sum[(2 k - 1) (2 (n - k) - 1) T[k - 1, i] T[n - k - 1, g - i], {k, 1, n - 1}, {i, 0, g}])/((n + 1)/6);
a[n_] := T[n, 10];
Table[a[n], {n, 20, 30}] (* Jean-François Alcover, Jul 20 2018 *)
-
\\ see A238396
Showing 1-10 of 11 results.
Comments