

A221992


Number of binary arrays indicating the locations of trailing edge maxima of a random lengthn 0..1 array extended with zeros and convolved with 1,4,6,4,1.


1



2, 3, 4, 6, 10, 15, 22, 35, 54, 81, 125, 193, 294, 450, 692, 1060, 1622, 2488, 3815, 5843, 8955, 13729, 21038, 32239, 49415, 75734, 116062, 177879, 272623, 417812, 640332, 981380, 1504053, 2305088, 3532772, 5414309, 8297912, 12717320, 19490493
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

Column 1 of A221999.


LINKS

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


FORMULA

Empirical: a(n) = a(n1) + 2*a(n3)  a(n4)  a(n6) + a(n7).
Empirical g.f.: x*(1 + x + x^2)*(2  x  x^3 + x^4) / (1  x  2*x^3 + x^4 + x^6  x^7).  Colin Barker, Aug 14 2018


EXAMPLE

Some solutions for n=7, one extended zero followed by filtered positions:
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....1....0....0....1....0....0....0....1....1....0....0....1
..0....0....1....0....0....0....1....0....0....0....1....0....0....0....0....0
..1....0....0....1....0....0....0....0....1....0....0....0....0....0....0....0
..0....0....0....0....1....1....0....0....0....1....1....0....0....0....0....1
..1....0....0....0....0....0....0....0....0....0....0....1....0....1....0....0
..0....0....0....0....0....0....0....0....1....1....0....0....1....0....1....0
..0....1....1....0....0....1....0....0....0....0....0....0....0....0....0....1
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0


CROSSREFS

Cf. A221999.
Sequence in context: A147788 A104977 A206742 * A221993 A221994 A222021
Adjacent sequences: A221989 A221990 A221991 * A221993 A221994 A221995


KEYWORD

nonn


AUTHOR

R. H. Hardin, Feb 03 2013


STATUS

approved



