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A188184 Number of strictly increasing arrangements of 6 numbers in -(n+4)..(n+4) with sum zero 1
32, 94, 227, 480, 920, 1636, 2739, 4370, 6698, 9926, 14293, 20076, 27594, 37212, 49341, 64444, 83036, 105690, 133037, 165772, 204654, 250510, 304239, 366814, 439284, 522780, 618513, 727782, 851974, 992568, 1151137, 1329352, 1528984 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 6 of A188181

LINKS

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

FORMULA

Empirical: a(n)=3*a(n-1)-2*a(n-2)-a(n-3)+2*a(n-5)-a(n-6)-a(n-7)+2*a(n-8)-a(n-10)-2*a(n-11)+3*a(n-12)-a(n-13).

Empirical: G.f. -x*(-32 +2*x -9*x^2 -19*x^3 -28*x^4 +x^5 +5*x^6 -17*x^7 +x^8 +10*x^9 +13*x^10 -23*x^11 +8*x^12) / ( (1+x) *(1+x+x^2) *(x^4+x^3+x^2+x+1) *(x-1)^6 ). - R. J. Mathar, Mar 26 2011

EXAMPLE

Some solutions for n=5

.-7...-9...-6...-4...-8...-7...-7...-6...-7...-6...-8...-9...-6...-6...-9...-8

.-5...-5...-4...-2...-6...-5...-2...-5...-3...-3...-3...-2...-3...-5...-6...-3

.-4....1...-1...-1....1...-4...-1...-2....0...-2...-2....0...-2...-4....1...-1

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

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

..9....6....5....4....8....8....7....7....6....7....9....5....7....8....7....8

CROSSREFS

Sequence in context: A228801 A220581 A124804 * A126386 A208635 A259715

Adjacent sequences:  A188181 A188182 A188183 * A188185 A188186 A188187

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 23 2011

STATUS

approved

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Last modified August 20 17:05 EDT 2017. Contains 290836 sequences.