A269921
Triangle read by rows: T(n,f) is the number of rooted maps with n edges and f faces on an orientable surface of genus 1.
Original entry on oeis.org
1, 10, 10, 70, 167, 70, 420, 1720, 1720, 420, 2310, 14065, 24164, 14065, 2310, 12012, 100156, 256116, 256116, 100156, 12012, 60060, 649950, 2278660, 3392843, 2278660, 649950, 60060, 291720, 3944928, 17970784, 36703824, 36703824, 17970784
Offset: 2
Triangle starts:
n\f [1] [2] [3] [4] [5] [6] [7]
[2] 1;
[3] 10, 10;
[4] 70, 167, 70;
[5] 420, 1720, 1720, 420;
[6] 2310, 14065, 24164, 14065, 2310;
[7] 12012, 100156, 256116, 256116, 100156, 12012;
[8] 60060, 649950, 2278660, 3392843, 2278660, 649950, 60060;
[9] ...
-
M = 9; G = 1; gMax[n_] := Min[Quotient[n, 2], G];
Q = Array[0&, {M + 1, M + 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_] := (Qset[0, 0, x]; For[n = 1, n <= Length[Q] - 1, n++, For[g = 0, g <= gMax[n], g++, 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[ Sum[(2*k - 1) * (2*(n - k) - 1) * Qget[k - 1, i] * Qget[n - k - 1, g - i], {i, 0, g}], {k, 1, n-1}]; Qset[n, g, (t1 + t2 + t3) * 6/(n+1)]]]);
Quadric[x];
(List @@@ Table[Qget[n - 1 + 2*G, G] // Expand, {n, 1, M + 1 - 2*G}]) /. x -> 1 // Flatten (* Jean-François Alcover, Jun 13 2017, adapted from PARI *)
-
N = 9; G = 1; gmax(n) = min(n\2, G);
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, length(Q)-1, 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('x);
concat(apply(p->Vecrev(p/'x), vector(N+1 - 2*G, n, Qget(n-1 + 2*G, G))))
A006295
Number of genus 1 rooted maps with 2 faces with n vertices.
Original entry on oeis.org
10, 167, 1720, 14065, 100156, 649950, 3944928, 22764165, 126264820, 678405090, 3550829360, 18182708362, 91392185080, 452077562620, 2205359390592, 10627956019245, 50668344988068, 239250231713210, 1120028580999440, 5202779260636958, 23998704563581000, 109991785264412452
Offset: 3
- 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.
-
Rest[CoefficientList[Series[(1 - Sqrt[1 - 4 x]) (11 + 12 x + 9 Sqrt[1 - 4 x]) / (4 (4 x - 1)^4), {x, 0, 40}], x]] (* Vincenzo Librandi, Jun 06 2017 *)
-
A000108_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-4*x))/(2*x);
A006295_ser(N) = {
my(y = A000108_ser(N+1)); y*(y-1)^3*(y^2 + 15*y - 6)/(y-2)^8;
};
Vec(A006295_ser(31)) \\ Gheorghe Coserea, Jun 04 2017
-
my(x = 'x + O('x^60)); Vec(x*(1-sqrt(1-4*x))*(11+12*x+9*sqrt(1-4*x))/(4*(4*x-1)^4)) \\ Michel Marcus, Jun 05 2017
A006296
Number of genus 1 rooted maps with 3 faces with n vertices.
Original entry on oeis.org
70, 1720, 24164, 256116, 2278660, 17970784, 129726760, 875029804, 5593305476, 34225196720, 201976335288, 1156128848680, 6447533938280, 35155923872640, 187959014565840, 987658610225052, 5110652802256260, 26084524995672080, 131501187454625560, 655590388845975000, 3235463376771463288, 15820770680078552000, 76708503479715247920, 369046200766330733880, 1762793459781859039080, 8364468224596427692896, 39445646133672676352560, 184956513528952419546448, 862615498961026097997392, 4003067488703222112053760, 18489846573354278755829152, 85028133934182275077421180, 389398354121840111751946628, 1776360539933013004774353872, 8073622060225813990245976280, 36567311475673299914222851832
Offset: 4
- 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.
-
Rest[CoefficientList[Series[(1 - Sqrt[1 - 4 x]) (45 + 152 x + (25 + 8 x) Sqrt[1 - 4 x]) / (2 (1 - 4 x)^(11 / 2)), {x, 0, 40}], x]] (* Vincenzo Librandi, Jun 06 2017 *)
-
A000108_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-4*x))/(2*x);
A006296_ser(N) = {
my(y = A000108_ser(N+1));
-2*y*(y-1)^4*(10*y^3 + 97*y^2 - 64*y - 8)/(y-2)^11;
};
Vec(A006296_ser(36)) \\ Gheorghe Coserea, Jun 04 2017
A287046
a(n) is the number of rooted maps with n edges and 6 faces on an orientable surface of genus 1.
Original entry on oeis.org
12012, 649950, 17970784, 344468530, 5188948072, 65723863196, 729734918432, 7302676928666, 67173739068760, 576218752277476, 4660202610532480, 35839052357422132, 263868150558327376, 1870153808268516280, 12816868756802256832, 85256107136168684650, 552171259884681058744
Offset: 7
-
Q[0, 1, 0] = 1; Q[n_, f_, g_] /; n < 0 || f < 0 || g < 0 = 0;
Q[n_, f_, g_] := Q[n, f, g] = 6/(n + 1) ((2 n - 1)/3 Q[n - 1, f, g] + (2 n - 1)/3 Q[n - 1, f - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 Q[n - 2, f, g - 1] + 1/2 Sum[l = n - k; Sum[v = f - u; Sum[j = g - i; Boole[l >= 1 && v >= 1 && j >= 0] (2 k - 1) (2 l - 1) Q[k - 1, u, i] Q[l - 1, v, j], {i, 0, g}], {u, 1, f}], {k, 1, n}]);
a[n_] := Q[n, 6, 1];
Table[a[n], {n, 7, 23}] (* Jean-François Alcover, Oct 17 2018 *)
-
A000108_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-4*x))/(2*x);
A287046_ser(N) = {
my(y = A000108_ser(N+1));
2*y*(y-1)^7*(28457*y^6 + 179171*y^5 - 222214*y^4 - 172512*y^3 + 257232*y^2 - 59904*y - 4224)/(y-2)^20;
};
Vec(A287046_ser(17))
A287047
a(n) is the number of rooted maps with n edges and 7 faces on an orientable surface of genus 1.
Original entry on oeis.org
60060, 3944928, 129726760, 2908358552, 50534154408, 729734918432, 9145847808784, 102432266545800, 1046677747672360, 9908748651241088, 87930943305742512, 738178726378902064, 5905479331377981200, 45289976937922983360, 334600965220354244896, 2391127223524518889064, 16585285393291515557928
Offset: 8
-
Q[0, 1, 0] = 1; Q[n_, f_, g_] /; n < 0 || f < 0 || g < 0 = 0;
Q[n_, f_, g_] := Q[n, f, g] = 6/(n + 1) ((2 n - 1)/3 Q[n - 1, f, g] + (2 n - 1)/3 Q[n - 1, f - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 Q[n - 2, f, g - 1] + 1/2 Sum[l = n - k; Sum[v = f - u; Sum[j = g - i; Boole[l >= 1 && v >= 1 && j >= 0] (2 k - 1) (2 l - 1) Q[k - 1, u, i] Q[l - 1, v, j], {i, 0, g}], {u, 1, f}], {k, 1, n}]);
a[n_] := Q[n, 7, 1];
Table[a[n], {n, 8, 24}] (* Jean-François Alcover, Oct 18 2018 *)
-
A000108_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-4*x))/(2*x);
A287047_ser(N) = {
my(y = A000108_ser(N+1));
-4*y*(y-1)^8*(184142*y^7 + 1083793*y^6 - 1540136*y^5 - 1481152*y^4 + 2626176*y^3 - 737232*y^2 - 184896*y + 64320)/(y-2)^23;
};
Vec(A287047_ser(17))
A287048
a(n) is the number of rooted maps with n edges and 8 faces on an orientable surface of genus 1.
Original entry on oeis.org
291720, 22764165, 875029804, 22620890127, 448035881592, 7302676928666, 102432266545800, 1274461449989715, 14373136466094880, 149314477245194262, 1446563778096423816, 13196809961724011350, 114253624700659216080, 944690705838217837620, 7498935691376059259344, 57398464959432306918747
Offset: 9
-
Q[0, 1, 0] = 1; Q[n_, f_, g_] /; n < 0 || f < 0 || g < 0 = 0;
Q[n_, f_, g_] := Q[n, f, g] = 6/(n + 1) ((2 n - 1)/3 Q[n - 1, f, g] + (2 n - 1)/3 Q[n - 1, f - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 Q[n - 2, f, g - 1] + 1/2 Sum[l = n - k; Sum[v = f - u; Sum[j = g - i; Boole[l >= 1 && v >= 1 && j >= 0] (2 k - 1) (2 l - 1) Q[k - 1, u, i] Q[l - 1, v, j], {i, 0, g}], {u, 1, f}], {k, 1, n}]);
a[n_] := Q[n, 8, 1];
Table[a[n], {n, 9, 25}] (* Jean-François Alcover, Oct 18 2018 *)
-
A000108_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-4*x))/(2*x);
A287048_ser(N) = {
my(y = A000108_ser(N+1));
y*(y-1)^9*(9370183*y^8 + 52321971*y^7 - 83853806*y^6 - 93946092*y^5 + 189910936*y^4 - 57493776*y^3 - 31383264*y^2 + 16878912*y - 1513344)/(y-2)^26;
};
Vec(A287048_ser(16))
A288071
a(n) is the number of rooted maps with n edges and 4 faces on an orientable surface of genus 1.
Original entry on oeis.org
420, 14065, 256116, 3392843, 36703824, 344468530, 2908358552, 22620890127, 164767964504, 1137369687454, 7506901051000, 47700234551918, 293370096957504, 1753945289216484, 10229201477344752, 58364244137596695, 326571194881454376, 1795631576981016038, 9718877491130813368, 51858415558095569962
Offset: 5
-
Q[0, 1, 0] = 1; Q[n_, f_, g_] /; n < 0 || f < 0 || g < 0 = 0;
Q[n_, f_, g_] := Q[n, f, g] = 6/(n + 1) ((2 n - 1)/3 Q[n - 1, f, g] + (2 n - 1)/3 Q[n - 1, f - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 Q[n - 2, f, g - 1] + 1/2 Sum[l = n - k; Sum[v = f - u; Sum[j = g - i; Boole[l >= 1 && v >= 1 && j >= 0] (2 k - 1) (2 l - 1) Q[k - 1, u, i] Q[l - 1, v, j], {i, 0, g}], {u, 1, f}], {k, 1, n}]);
a[n_] := Q[n, 4, 1];
Table[a[n], {n, 5, 24}] (* Jean-François Alcover, Oct 18 2018 *)
-
A000108_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-4*x))/(2*x);
A288071_ser(N) = {
my(y = A000108_ser(N+1));
y*(y-1)^5*(307*y^4 + 2411*y^3 - 2094*y^2 - 708*y + 504)/(y-2)^14;
};
Vec(A288071_ser(20))
A288072
a(n) is the number of rooted maps with n edges and 5 faces on an orientable surface of genus 1.
Original entry on oeis.org
2310, 100156, 2278660, 36703824, 472592916, 5188948072, 50534154408, 448035881592, 3682811916980, 28442316247080, 208462422428152, 1461307573813824, 9857665477085832, 64309102366765200, 407372683115470800, 2514120288996270024, 15159074541052024308, 89512241718624419624
Offset: 6
-
Q[0, 1, 0] = 1; Q[n_, f_, g_] /; n < 0 || f < 0 || g < 0 = 0;
Q[n_, f_, g_] := Q[n, f, g] = 6/(n + 1) ((2 n - 1)/3 Q[n - 1, f, g] + (2 n - 1)/3 Q[n - 1, f - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 Q[n - 2, f, g - 1] + 1/2 Sum[l = n - k; Sum[v = f - u; Sum[j = g - i; Boole[l >= 1 && v >= 1 && j >= 0] (2 k - 1) (2 l - 1) Q[k - 1, u, i] Q[l - 1, v, j], {i, 0, g}], {u, 1, f}], {k, 1, n}]);
a[n_] := Q[n, 5, 1];
Table[a[n], {n, 6, 23}] (* Jean-François Alcover, Oct 18 2018 *)
-
A000108_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-4*x))/(2*x);
A288072_ser(N) = {
my(y = A000108_ser(N+1));
-2*y*(y-1)^6*(2140*y^5 + 14751*y^4 - 15604*y^3 - 8820*y^2 + 10176*y - 1488)/(y-2)^17;
};
Vec(A288072_ser(18))
A288074
a(n) is the number of rooted maps with n edges and 10 faces on an orientable surface of genus 1.
Original entry on oeis.org
6466460, 678405090, 34225196720, 1137369687454, 28442316247080, 576218752277476, 9908748651241088, 149314477245194262, 2017523504473479992, 24868664942648145372, 283389619978690157408, 3017066587822315930220, 30265092793614787511376, 288055728071446557904968, 2616366012933033221518720
Offset: 11
-
Q[0, 1, 0] = 1; Q[n_, f_, g_] /; n < 0 || f < 0 || g < 0 = 0;
Q[n_, f_, g_] := Q[n, f, g] = 6/(n + 1) ((2 n - 1)/3 Q[n - 1, f, g] + (2 n - 1)/3 Q[n - 1, f - 1, g] + (2 n - 3) (2 n - 2) (2 n - 1)/12 Q[n - 2, f, g - 1] + 1/2 Sum[l = n - k; Sum[v = f - u; Sum[j = g - i; Boole[l >= 1 && v >= 1 && j >= 0] (2 k - 1) (2 l - 1) Q[k - 1, u, i] Q[l - 1, v, j], {i, 0, g}], {u, 1, f}], {k, 1, n}]);
a[n_] := Q[n, 10, 1];
Table[a[n], {n, 11, 25}] (* Jean-François Alcover, Oct 18 2018 *)
-
A000108_ser(N) = my(x='x+O('x^(N+1))); (1 - sqrt(1-4*x))/(2*x);
A288074_ser(N) = {
my(y = A000108_ser(N+1));
2*y*(y-1)^11*(734641583*y^10 + 3795452665*y^9 - 7483071778*y^8 - 10235465624*y^7 + 25178445968*y^6 - 7563355856*y^5 - 11624244832*y^4 + 8854962048*y^3 - 1433163264*y^2 - 286758144*y + 65790464)/(y-2)^32;
};
Vec(A288074_ser(15))
Showing 1-9 of 9 results.
Comments