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A183900 Number of nondecreasing arrangements of n+3 numbers in 0..5 with each number being the sum mod 6 of three others. 1
3, 24, 130, 364, 771, 1386, 2281, 3534, 5236, 7492, 10422, 14162, 18865, 24702, 31863, 40558, 51018, 63496, 78268, 95634, 115919, 139474, 166677, 197934, 233680, 274380, 320530, 372658, 431325, 497126, 570691, 652686, 743814, 844816, 956472, 1079602 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A183904.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..57

FORMULA

Empirical: a(n) = (1/120)*n^5 + (1/4)*n^4 + (71/24)*n^3 + (57/4)*n^2 - (262/15)*n - 50 for n>4.

Conjectures from Colin Barker, Apr 05 2018: (Start)

G.f.: x*(3 + 6*x + 31*x^2 - 116*x^3 + 102*x^4 - 38*x^5 + 59*x^6 - 78*x^7 + 38*x^8 - 6*x^9) / (1 - x)^6.

a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>10.

(End)

EXAMPLE

Some solutions for n=2:

..0....1....0....0....0....0....0....0....0....0....0....3....1....3....0....1

..2....3....0....1....0....0....0....1....2....1....0....3....3....3....2....1

..4....5....2....3....2....2....0....1....4....2....4....5....3....3....2....1

..4....5....4....4....2....2....0....2....5....3....4....5....5....3....2....3

..4....5....4....5....4....2....0....4....5....4....4....5....5....3....4....3

CROSSREFS

Cf. A183904.

Sequence in context: A319097 A326789 A305543 * A001089 A069515 A206949

Adjacent sequences:  A183897 A183898 A183899 * A183901 A183902 A183903

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 07 2011

STATUS

approved

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Last modified February 22 17:14 EST 2020. Contains 332140 sequences. (Running on oeis4.)