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A245160 Number of length n 0..5 arrays with new values introduced in order from both ends. 1
1, 1, 2, 4, 9, 23, 65, 199, 654, 2296, 8569, 33825, 140580, 612890, 2794159, 13280627, 65597882, 335521900, 1770176005, 9593485125, 53183385680, 300371056446, 1721926382427, 9987133305239, 58446578859494, 344361988828048 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

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

FORMULA

Empirical: a(n) = 26*a(n-1) - 290*a(n-2) + 1820*a(n-3) - 7073*a(n-4) + 17618*a(n-5) - 28060*a(n-6) + 27480*a(n-7) - 14976*a(n-8) + 3456*a(n-9) for n>10.

Empirical g.f.: x*(1 - 25*x + 266*x^2 - 1578*x^3 + 5738*x^4 - 13236*x^5 + 19385*x^6 - 17565*x^7 + 9271*x^8 - 2381*x^9) / ((1 - x)^2*(1 - 2*x)^2*(1 - 3*x)^2*(1 - 4*x)^2*(1 - 6*x)). - Colin Barker, Nov 03 2018

EXAMPLE

Some solutions for n=7:

..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

..0....1....1....1....1....1....1....1....0....1....0....1....1....1....1....0

..1....2....1....0....0....0....0....0....1....2....1....0....0....2....1....1

..0....2....0....0....2....1....0....1....2....2....2....0....1....2....2....2

..2....2....0....0....0....0....0....0....0....0....1....1....1....1....2....2

..1....1....1....0....1....1....1....0....1....1....0....0....0....0....1....1

..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

CROSSREFS

Column 5 of A245163.

Sequence in context: A014137 A245158 A245159 * A245161 A245162 A007476

Adjacent sequences:  A245157 A245158 A245159 * A245161 A245162 A245163

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 12 2014

STATUS

approved

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Last modified January 19 03:39 EST 2019. Contains 319284 sequences. (Running on oeis4.)