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A188238 Number of nondecreasing arrangements of 5 numbers in -(n+3)..(n+3) with sum zero and not more than two numbers equal. 1
58, 119, 221, 374, 598, 903, 1317, 1852, 2540, 3397, 4459, 5744, 7296, 9133, 11303, 13830, 16766, 20135, 23997, 28378, 33342, 38919, 45177, 52148, 59908, 68489, 77971, 88392, 99836, 112341, 125999, 140850, 156990, 174463, 193369, 213754, 235726 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 5 of A188236.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = 2*a(n-1) - a(n-3) - 2*a(n-5) + 2*a(n-6) + a(n-8) - 2*a(n-10) + a(n-11).

Empirical g.f.: x*(58 + 3*x - 17*x^2 - 10*x^3 - 31*x^4 + 44*x^5 + 7*x^6 + 20*x^7 - 13*x^8 - 37*x^9 + 22*x^10) / ((1 - x)^5*(1 + x)^2*(1 + x^2)*(1 + x + x^2)). - Colin Barker, Apr 27 2018

EXAMPLE

Some solutions for n=4:

.-4...-4...-7...-3...-7...-5...-5...-7...-3...-4...-4...-6...-5...-3...-4...-5

.-2...-3...-1...-1...-6...-3...-2...-6...-3...-2...-1...-4...-1...-2...-4...-1

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

..4....3....2....1....5....3....1....6....1....1....2....3....0....0....3....0

..4....7....5....3....7....5....7....6....6....6....2....4....7....6....4....6

CROSSREFS

Cf. A188236.

Sequence in context: A124680 A181462 A260603 * A044245 A044626 A039536

Adjacent sequences:  A188235 A188236 A188237 * A188239 A188240 A188241

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 24 2011

STATUS

approved

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Last modified July 23 13:58 EDT 2019. Contains 325254 sequences. (Running on oeis4.)