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 1-6 of 6 results.

A223639 Number of n X 3 0..1 arrays with rows, columns, diagonals and antidiagonals unimodal.

Original entry on oeis.org

7, 49, 218, 726, 2014, 4904, 10797, 21917, 41601, 74635, 127636, 209480, 331776, 509386, 760991, 1109703, 1583723, 2217045, 3050206, 4131082, 5515730, 7269276, 9466849, 12194561, 15550533, 19645967, 24606264, 30572188, 37701076, 46168094
Offset: 1

Views

Author

R. H. Hardin, Mar 24 2013

Keywords

Comments

Column 3 of A223644.

Examples

			Some solutions for n=4:
..0..1..1....1..1..0....0..0..0....0..1..0....0..1..1....0..1..0....0..0..1
..0..1..1....1..1..0....1..1..0....1..1..0....1..1..0....1..1..0....0..0..1
..1..1..0....1..1..0....1..1..0....0..1..1....0..0..0....1..1..0....0..1..1
..1..0..0....0..0..1....0..0..1....0..0..1....0..0..0....1..0..0....0..1..1
		

Crossrefs

Cf. A223644.

Formula

Empirical: a(n) = (23/360)*n^6 - (3/40)*n^5 + (31/18)*n^4 + (5/8)*n^3 + (1517/360)*n^2 - (51/20)*n + 3.
Conjectures from Colin Barker, Aug 22 2018: (Start)
G.f.: x*(7 + 22*x^2 - 16*x^3 + 40*x^4 - 10*x^5 + 3*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) for n>7.
(End)

A223640 Number of n X 4 0..1 arrays with rows, columns, diagonals and antidiagonals unimodal.

Original entry on oeis.org

11, 121, 726, 2962, 9808, 28450, 74599, 179991, 404599, 855417, 1714062, 3275798, 6002946, 10596004, 18086161, 29953249, 48273537, 75902131, 116695104, 175776840, 259858436, 377613366, 540116971, 761356699, 1058820379, 1454170173
Offset: 1

Views

Author

R. H. Hardin, Mar 24 2013

Keywords

Comments

Column 4 of A223644.

Examples

			Some solutions for n=4:
..0..1..0..0....1..1..0..0....1..0..0..0....0..1..1..1....0..0..1..1
..0..1..1..1....1..1..1..0....0..1..0..0....0..0..1..1....0..1..1..1
..0..1..1..0....0..1..1..1....0..0..0..0....0..0..0..0....0..0..0..0
..0..0..1..0....0..0..0..1....0..0..1..0....0..0..0..0....0..0..0..0
		

Crossrefs

Cf. A223644.

Formula

Empirical: a(n) = (1/112)*n^8 - (19/210)*n^7 + (107/90)*n^6 - (197/40)*n^5 + (2219/144)*n^4 + (5093/120)*n^3 - (868411/2520)*n^2 + (417721/420)*n - 1091 for n>4.
Conjectures from Colin Barker, Aug 22 2018: (Start)
G.f.: x*(11 + 22*x + 33*x^2 - 140*x^3 + 508*x^4 - 314*x^5 - 17*x^6 + 432*x^7 - 233*x^8 + 28*x^9 + 56*x^10 - 28*x^11 + 2*x^12) / (1 - x)^9.
a(n) = 9*a(n-1) - 36*a(n-2) + 84*a(n-3) - 126*a(n-4) + 126*a(n-5) - 84*a(n-6) + 36*a(n-7) - 9*a(n-8) + a(n-9) for n>13.
(End)

A223641 Number of nX5 0..1 arrays with rows, columns, diagonals and antidiagonals unimodal.

Original entry on oeis.org

16, 256, 2014, 9808, 36947, 120307, 354726, 967582, 2469396, 5941152, 13555296, 29475566, 61346859, 122671803, 236477826, 440811016, 796753648, 1399853788, 2396080742, 4003682172, 6542620323, 10473608867, 16449161244, 25379498938
Offset: 1

Views

Author

R. H. Hardin Mar 24 2013

Keywords

Comments

Column 5 of A223644

Examples

			Some solutions for n=4
..0..0..1..0..0....0..0..1..1..0....1..1..1..1..1....0..1..0..0..0
..0..1..1..1..0....0..0..1..1..1....1..1..1..1..1....0..1..0..0..0
..0..0..1..1..1....0..0..1..1..0....0..1..1..1..1....1..0..0..0..0
..0..0..1..0..0....0..0..1..1..0....0..0..1..0..0....1..0..0..0..0
		

Formula

Empirical: a(n) = (359/453600)*n^10 - (391/18144)*n^9 + (27901/60480)*n^8 - (5318/945)*n^7 + (220373/5400)*n^6 + (42079/4320)*n^5 - (611182913/181440)*n^4 + (204761033/5670)*n^3 - (1618325179/8400)*n^2 + (680702213/1260)*n - 629380 for n>7

A223642 Number of nX6 0..1 arrays with rows, columns, diagonals and antidiagonals unimodal.

Original entry on oeis.org

22, 484, 4904, 28450, 120307, 428187, 1370104, 4063584, 11337648, 29980136, 75501066, 181755554, 419574383, 931417149, 1993443114, 4122964868, 8258744026, 16054980456, 30348305906, 55882034882, 100405014805, 176305599685
Offset: 1

Views

Author

R. H. Hardin Mar 24 2013

Keywords

Comments

Column 6 of A223644

Examples

			Some solutions for n=4
..0..1..1..1..1..1....0..0..0..0..1..1....0..0..0..1..0..0....0..1..0..0..0..0
..1..1..1..1..1..1....0..1..1..1..1..1....1..1..1..1..1..0....1..1..1..1..0..0
..1..1..1..1..1..1....0..1..1..1..1..1....0..0..1..1..1..1....0..1..1..1..0..0
..0..0..0..1..1..0....0..0..0..0..0..0....0..0..0..0..1..0....0..1..1..0..0..0
		

Formula

Empirical: a(n) = (271/5443200)*n^12 - (5527/1995840)*n^11 + (55709/544320)*n^10 - (179285/72576)*n^9 + (69131681/1814400)*n^8 - (2290717/10080)*n^7 - (649163341/136080)*n^6 + (54977562187/362880)*n^5 - (2886586169891/1360800)*n^4 + (1624780719439/90720)*n^3 - (17508153293/189)*n^2 + (926735309999/3465)*n - 321893740 for n>13

A223643 Number of nX7 0..1 arrays with rows, columns, diagonals and antidiagonals unimodal.

Original entry on oeis.org

29, 841, 10797, 74599, 354726, 1370104, 4682514, 14767708, 43862845, 124004457, 335617558, 872372014, 2182675327, 5267049151, 12280118231, 27708360959, 60600014150, 128659653568, 265553503693, 533599565121, 1045268782162
Offset: 1

Views

Author

R. H. Hardin Mar 24 2013

Keywords

Comments

Column 7 of A223644

Examples

			Some solutions for n=4
..0..0..0..1..1..0..0....0..1..1..0..0..0..0....0..0..1..0..0..0..0
..0..0..1..1..1..1..1....0..1..1..1..1..1..0....0..1..1..1..1..1..1
..0..1..1..1..1..1..0....0..0..0..1..1..1..0....1..1..1..1..1..1..0
..0..0..0..0..1..0..0....0..0..0..0..0..0..1....0..0..0..0..1..0..0
		

Formula

Empirical: a(n) = (503/209563200)*n^14 - (185069/778377600)*n^13 + (1733819/119750400)*n^12 - (7176551/11975040)*n^11 + (36644381/2177280)*n^10 - (480531353/1814400)*n^9 - (76780811581/76204800)*n^8 + (29262582467/155520)*n^7 - (62420351374933/10886400)*n^6 + (281872655928541/2721600)*n^5 - (74234681724454753/59875200)*n^4 + (3261809312979967/332640)*n^3 - (557318597695013723/11642400)*n^2 + (14542780178794541/120120)*n - 90173668357 for n>19

A223638 Number of n X n 0..1 arrays with rows, columns, diagonals and antidiagonals unimodal.

Original entry on oeis.org

2, 16, 218, 2962, 36947, 428187, 4682514, 49045356, 497721760, 4944054774
Offset: 1

Views

Author

R. H. Hardin Mar 24 2013

Keywords

Comments

Diagonal of A223644

Examples

			Some solutions for n=4
..0..0..0..1....0..0..1..0....1..1..1..0....0..0..0..0....0..0..0..1
..0..0..1..1....1..1..0..0....0..1..1..0....1..0..0..0....1..1..1..0
..0..1..1..1....0..1..0..0....0..0..1..0....0..0..0..1....0..0..0..0
..0..1..1..0....0..1..0..0....0..0..0..1....0..1..0..0....0..0..0..0
		
Showing 1-6 of 6 results.