A245162 Number of length n 0..7 arrays with new values introduced in order from both ends

1, 1, 2, 4, 9, 23, 65, 199, 654, 2296, 8569, 33825, 140581, 612933, 2795182, 13298464, 65852872, 338694406, 1805809431, 9963758843, 56805378239, 334156440067, 2025424520548, 12633195093794, 80976535864874, 532652296499548

Offset

1,3

Comments

Column 7 of A245163

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 50*a(n-1) -1127*a(n-2) +15148*a(n-3) -135303*a(n-4) +846930*a(n-5) -3816041*a(n-6) +12508144*a(n-7) -29761816*a(n-8) +50647520*a(n-9) -59753232*a(n-10) +46142208*a(n-11) -20839680*a(n-12) +4147200*a(n-13) for n>14

Example

Some solutions for n=7
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....0....0....1....1....1....1....1....1....0....1....0....0....1....0....1
..0....0....1....1....0....1....2....2....1....1....1....1....0....0....0....1
..2....0....2....0....1....1....3....1....1....0....2....1....1....0....0....1
..0....1....1....1....1....0....2....1....1....0....1....1....1....1....0....0
..1....1....1....0....0....1....1....1....1....1....1....1....1....0....1....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

Crossrefs

Sequence in context: A245159 A245160 A245161 * A007476 A202552 A272301

Adjacent sequences: A245159 A245160 A245161 * A245163 A245164 A245165

Keyword

nonn

Author

R. H. Hardin, Jul 12 2014

Status

approved