A294791
Triangle read by rows, 1 <= k <= n: T(n,k) = non-isomorphic colorings of a toroidal n X k grid using exactly two colors under translational symmetry and swappable colors.
Original entry on oeis.org
0, 1, 4, 1, 7, 31, 3, 23, 179, 2107, 3, 55, 1095, 26271, 671103, 7, 189, 7327, 350063, 17896831, 954459519, 9, 595, 49939, 4794087, 490853415, 52357746895, 5744387279871, 19, 2101, 349715, 67115111, 13743921631, 2932032057731, 643371380132743, 144115188277194943, 29, 7315, 2485591, 954444607, 390937468407, 166799988703927, 73201365371896619
Offset: 1
For the 2 X 2 grid and two colors we find T(2,2) = 4:
+---+ +---+ +---+ +---+
|X| | |X| | |X|X| |X| |
+-+-+ +-+-+ +-+-+ +-+-+
| | | | |X| | | | |X| |
+-+-+ +-+-+ +-+-+ +-+-+
- F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
A294793
Triangle read by rows, 1 <= k <= n: T(n,k) = non-isomorphic colorings of a toroidal n X k grid using exactly four colors under translational symmetry and swappable colors.
Original entry on oeis.org
0, 0, 1, 0, 13, 874, 1, 235, 51075, 10741819, 2, 3437, 2823766, 2261625725, 1870851589562, 13, 51275, 155495153, 486711524815, 1600136051453135, 5465007068038102643, 50, 742651, 8643289534, 107092397450897, 1405227969932349726, 19188864521773558375127, 269482732023591671431784330, 221, 10741763, 486710971595, 24009547064476683
Offset: 1
- F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
A294684
Triangle read by rows: T(n,k) is the number of non-isomorphic colorings of a toroidal n X k grid using exactly two colors under translational symmetry, 1 <= k <= n.
Original entry on oeis.org
0, 1, 5, 2, 12, 62, 4, 38, 350, 4154, 6, 106, 2190, 52486, 1342206, 12, 360, 14622, 699598, 35792566, 1908897150, 18, 1180, 99878, 9587578, 981706830, 104715443850, 11488774559742, 34, 4148, 699250, 134223974, 27487816990, 5864063066498, 1286742755471398, 288230376353050814
Offset: 1
Triangle begins:
0;
1, 5;
2, 12, 62;
4, 38, 350, 4154;
6, 106, 2190, 52486, 1342206;
12, 360, 14622, 699598, 35792566, 1908897150;
18, 1180, 99878, 9587578, 981706830, 104715443850, 11488774559742;
...
For the 2 X 2 and two colors we find
+---+ +---+ +---+ +---+ +---+
|X| | | |X| |X| | |X|X| |X| |
+-+-+ +-+-+ +-+-+ +-+-+ +-+-+
| | | |X|X| | |X| | | | |X| |
+-+-+ +-+-+ +-+-+ +-+-+ +-+-+
- F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
-
With[{Q = 2}, Table[(Q!/n/k) Sum[Sum[EulerPhi[d] EulerPhi[f] StirlingS2[GCD[d, f] (n/d) (k/f), Q], {f, Divisors@ k}], {d, Divisors@ n}], {n, 8}, {k, n}]] // Flatten (* Michael De Vlieger, Nov 08 2017 *)
-
T(n,m) = {2*sumdiv(n, d, sumdiv(m, e, eulerphi(d) * eulerphi(e) * stirling(n*m/lcm(d,e), 2, 2) ))/(n*m)} \\ Andrew Howroyd, Oct 05 2024
A294685
Triangle read by rows: T(n,k) is the number of non-isomorphic colorings of a toroidal n X k grid using exactly three colors under translational symmetry, 1 <= k <= n.
Original entry on oeis.org
0, 0, 9, 2, 91, 2022, 9, 738, 43315, 2679246, 30, 5613, 950062, 174184755, 33887517990, 91, 43404, 21480921, 11765865678, 6862930841141, 4169289730628814, 258, 338259, 497812638, 816999710223, 1429469771994078, 2605213713043722909, 4883659745750360600262, 729, 2679228, 11765822365, 57906482267826, 303941554100145501
Offset: 1
Triangle begins:
0;
0, 9;
2, 91, 2022;
9, 738, 43315, 2679246;
30, 5613, 950062, 174184755, 33887517990;
91, 43404, 21480921, 11765865678, 6862930841141, 4169289730628814;
...
- F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
-
T(n,m)=6*sumdiv(n, d, sumdiv(m, e, eulerphi(d) * eulerphi(e) * stirling(n*m/lcm(d,e), 3, 2) ))/(n*m) \\ Andrew Howroyd, Oct 05 2024
A294686
Triangle read by rows: T(n,k) is the number of non-isomorphic colorings of a toroidal n X k grid using exactly four colors under translational symmetry, 1 <= k <= n.
Original entry on oeis.org
0, 0, 6, 0, 260, 20720, 6, 5112, 1223136, 257706024, 48, 81876, 67769552, 54278580036, 44900438149488, 260, 1223396, 3731753700, 11681058472672, 38403264917970196, 131160169581733489616, 1200, 17815020, 207438938000, 2570217454576416, 33725471278376393424, 460532748521625850986660, 6467585568566200114362823920, 5106, 257706012, 11681057249536, 576229125971686224
Offset: 1
Triangle begins:
0;
0, 6;
0, 260, 20720;
6, 5112, 1223136, 257706024;
48, 81876, 67769552, 54278580036, 44900438149488;
260, 1223396, 3731753700, 11681058472672, 38403264917970196, 131160169581733489616;
...
- F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
-
T(n,m)=my(k=4); k!*sumdiv(n, d, sumdiv(m, e, eulerphi(d) * eulerphi(e) * stirling(n*m/lcm(d,e), k, 2) ))/(n*m) \\ Andrew Howroyd, Oct 05 2024
A294687
Triangle read by rows: T(n,k) is the number of non-isomorphic colorings of a toroidal n X k grid using exactly five colors under translational symmetry, 1 <= k <= n.
Original entry on oeis.org
0, 0, 0, 0, 300, 92680, 0, 15750, 13794150, 8221452750, 24, 510312, 1686135376, 4495236798162, 11696087875731720, 300, 13794450, 193054017440, 2425003938178050, 30852000867277668428, 403564024914127655401650, 2400, 343501500, 21664357535320, 1317601563731383350, 82985159653854019928352, 5411356249329837891442095560
Offset: 1
Triangle begins:
0;
0, 0;
0, 300, 92680;
0, 15750, 13794150, 8221452750;
24, 510312, 1686135376, 4495236798162, 11696087875731720;
...
- F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
-
T(n,m)=my(k=5); k!*sumdiv(n, d, sumdiv(m, e, eulerphi(d) * eulerphi(e) * stirling(n*m/lcm(d,e), k, 2) ))/(n*m) \\ Andrew Howroyd, Oct 05 2024
A294794
Triangle read by rows, 1 <= k <= n: T(n,k) = non-isomorphic colorings of a toroidal n X k grid using exactly five colors under translational symmetry and swappable colors.
Original entry on oeis.org
0, 0, 0, 0, 3, 775, 0, 145, 115100, 68522769, 1, 4281, 14051164, 37460388596, 97467398965031, 3, 115381, 1608801153, 20208371722051, 257100007425866689, 3363033541015148835823, 20, 2863227, 180536313547, 10980013072900632, 691542997115450167856, 45094635411084308447578413, 3020745549854628001139950947779, 136, 68522707
Offset: 1
- F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
A295197
Triangle read by rows: T(n,k) is the number of non-isomorphic colorings of a toroidal n X k grid using any number of swappable colors, 1 <= k <= n.
Original entry on oeis.org
1, 2, 9, 3, 43, 2387, 7, 587, 351773, 655089857, 12, 11703, 92197523, 2586209749712, 185543613289205809, 43, 352902, 37893376167, 18581620064907130, 28224967150633208580385, 106103186941524316132396201360, 127, 13639372, 22612848403571, 220019264470242220839, 8045720086273150473238405274, 851013076163633746725692124186472539, 218900758256599151027392153440612298654753249
Offset: 1
The two-by-two with swappable colors has one monochrome coloring, four colorings with two colors, three colorings with three colors (determined by the color that appears twice) and one coloring with four colors.
Triangle begins:
1;
2, 9;
3, 43, 2387;
7, 587, 351773, 655089857;
12, 11703, 92197523, 2586209749712, 185543613289205809;
...
- F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
-
\\ B(m,n) is A162663(n,m).
B(m,n)={n!*polcoef(exp(sumdiv(m,d, (exp(d*x + O(x*x^n))-1)/d)), n)}
T(n,k)={my(v=vector(lcm(n,k))); fordiv(n,d, fordiv(k,e, v[lcm(d,e)] += eulerphi(d) * eulerphi(e) )); sumdiv(#v, g, v[g]*B(g,n*k/g))/(n*k)} \\ Andrew Howroyd, Oct 06 2024
A376808
Number of non-isomorphic colorings of a toroidal n X n grid using any number of swappable colors.
Original entry on oeis.org
1, 9, 2387, 655089857, 185543613289205809, 106103186941524316132396201360, 218900758256599151027392153440612298654753249, 2689595989958732045849530682270318547733917269644639109073775285
Offset: 1
For the 2x2 we find
+-+-+ +-+-+ +-+-+ +-+-+ +-+-+
|X|X| |X|X| |X|X| |X| | |X| |
+-+-+ +-+-+ +-+-+ +-+-+ +-+-+
|X|X| |X| | | | | |X| | | |X|
+-+-+ +-+-+ +-+-+ +-+-+ +-+-+
+-+-+ +-+-+ +-+-+ +-+-+
|X|Y| |X| | |X| | |X|Y|
+-+-+ +-+-+ +-+-+ +-+-+
| | | |Y| | | |Y| |Z| |
+-+-+ +-+-+ +-+-+ +-+-+
so a(2) = 9.
- F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
A376748
Number of non-isomorphic colorings of a toroidal n X n grid using exactly three swappable colors.
Original entry on oeis.org
0, 3, 345, 447156, 5647919665, 694881637942816, 813943290958393433377, 8941884948534360647405572800, 912400181570021638669407666368774097, 858962534553352212055863239761275173880606456, 7425662396340624836407113113710889289196975262054947345, 587417576454184723055270940786413231085263155884260701824558793960
Offset: 1
- F. Harary and E. Palmer, Graphical Enumeration, Academic Press, 1973.
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