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 1-5 of 5 results.

A217978 Number of n X 4 arrays of the minimum value of corresponding elements and their horizontal, vertical, diagonal or antidiagonal neighbors in a random 0..1 n X 4 array.

Original entry on oeis.org

6, 6, 36, 98, 362, 1180, 4046, 13594, 46052, 155494, 525730, 1776548, 6004634, 20293538, 68587432, 231806206, 783444274, 2647830256, 8948960354, 30245088582, 102220312680, 345477304222, 1167620873294, 3946246173440, 13337256366382
Offset: 1

Views

Author

R. H. Hardin, Oct 16 2012

Keywords

Comments

Column 4 of A217982.

Examples

			Some solutions for n=3:
..1..1..0..0....0..0..0..1....1..1..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....0..0..0..0
..0..0..1..1....1..0..0..0....0..0..0..1....1..0..0..0....0..0..0..0
		

Crossrefs

Cf. A217982.

Formula

Empirical: a(n) = 2*a(n-1) + 5*a(n-2) + a(n-3) - 5*a(n-4) - 8*a(n-5) + a(n-6) + 2*a(n-7).
Empirical g.f.: 2*x*(3 - 3*x - 3*x^2 - 5*x^3 + 5*x^4 + 4*x^5) / (1 - 2*x - 5*x^2 - x^3 + 5*x^4 + 8*x^5 - x^6 - 2*x^7). - Colin Barker, Jul 23 2018

A217979 Number of nX5 arrays of the minimum value of corresponding elements and their horizontal, vertical, diagonal or antidiagonal neighbors in a random 0..1 nX5 array.

Original entry on oeis.org

10, 10, 100, 362, 1942, 8872, 43258, 205446, 986288, 4714274, 22573862, 108013892, 516992146, 2474201538, 11841537864, 56672476422, 271231398802, 1298094250056, 6212595977182, 29733069165822, 142300516403984, 681040858862718
Offset: 1

Views

Author

R. H. Hardin Oct 16 2012

Keywords

Comments

Column 5 of A217982

Examples

			Some solutions for n=3
..1..1..1..0..0....1..1..0..0..0....1..1..0..0..0....1..0..0..0..0
..0..0..1..0..0....1..0..0..0..0....1..0..0..0..0....1..0..0..0..0
..0..0..1..1..1....1..0..0..0..0....1..0..0..0..1....1..1..1..1..1
		

Formula

Empirical: a(n) = 3*a(n-1) +10*a(n-2) +a(n-3) -28*a(n-4) -58*a(n-5) +41*a(n-6) +39*a(n-7) -50*a(n-8) -9*a(n-9) +100*a(n-10) +368*a(n-11) -439*a(n-12) -51*a(n-13) +370*a(n-14) -249*a(n-15) -56*a(n-16) +106*a(n-17) -33*a(n-18) -7*a(n-19) +6*a(n-20) +a(n-21)

A217980 Number of nX6 arrays of the minimum value of corresponding elements and their horizontal, vertical, diagonal or antidiagonal neighbors in a random 0..1 nX6 array.

Original entry on oeis.org

16, 16, 256, 1180, 8872, 54504, 363728, 2347480, 15361400, 99957900, 651962620, 4248252712, 27693131900, 180493901576, 1176474695224, 7668147995040, 49980828130368, 325772423519628, 2123371872316720, 13840043094715540
Offset: 1

Views

Author

R. H. Hardin Oct 16 2012

Keywords

Comments

Column 6 of A217982

Examples

			Some solutions for n=3
..1..1..0..0..0..1....0..0..0..0..0..1....1..1..0..0..0..1....1..1..0..0..0..0
..0..0..0..0..0..0....0..0..0..0..0..1....1..1..0..0..0..0....0..0..0..0..0..0
..0..0..1..1..0..0....0..0..0..0..0..1....1..1..1..0..0..0....0..0..1..1..0..0
		

Formula

Empirical: a(n) = 5*a(n-1) +20*a(n-2) -26*a(n-3) -243*a(n-4) -402*a(n-5) +1359*a(n-6) +3862*a(n-7) +575*a(n-8) -14159*a(n-9) -23730*a(n-10) +21635*a(n-11) +49428*a(n-12) +39959*a(n-13) -70045*a(n-14) -163116*a(n-15) +162408*a(n-16) +246212*a(n-17) -242465*a(n-18) -333744*a(n-19) +159949*a(n-20) +337852*a(n-21) -38088*a(n-22) -156828*a(n-23) -5419*a(n-24) +49017*a(n-25) +4621*a(n-26) -24626*a(n-27) -9053*a(n-28) +3845*a(n-29) +4770*a(n-30) +619*a(n-31) -302*a(n-32) -153*a(n-33) -20*a(n-34) +12*a(n-35)

A217981 Number of nX7 arrays of the minimum value of corresponding elements and their horizontal, vertical, diagonal or antidiagonal neighbors in a random 0..1 nX7 array.

Original entry on oeis.org

26, 26, 676, 4046, 43258, 363728, 3375350, 30097566, 272859916, 2457033362, 22187715406, 200128757472, 1805997462058, 16294400662942, 147026523230292, 1326594311794394, 11969797169381830, 108002268912887340
Offset: 1

Views

Author

R. H. Hardin Oct 16 2012

Keywords

Comments

Column 7 of A217982

Examples

			Some solutions for n=3
..0..0..0..1..1..0..0....1..1..1..0..0..0..1....0..0..0..0..0..0..1
..0..0..0..0..0..0..0....1..1..1..0..0..0..1....0..0..0..0..0..0..0
..1..0..0..0..0..1..1....1..1..1..0..0..0..1....0..0..0..1..1..0..0
		

A217977 Number of n X n arrays of the minimum value of corresponding elements and their horizontal, vertical, diagonal or antidiagonal neighbors in a random 0..1 n X n array.

Original entry on oeis.org

2, 2, 16, 98, 1942, 54504, 3375350, 368335390, 79138501972, 31734389399738, 24359808536352098, 35370314418915229140
Offset: 1

Views

Author

R. H. Hardin Oct 16 2012

Keywords

Comments

Diagonal of A217982

Examples

			Some solutions for n=3
..0..0..0....0..0..0....0..0..0....0..0..1....1..0..0....1..1..1....0..0..1
..0..0..0....0..0..0....0..0..0....0..0..1....0..0..0....0..0..1....0..0..0
..1..1..1....0..0..0....1..0..0....0..0..1....0..0..0....0..0..1....1..0..0
		
Showing 1-5 of 5 results.