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A247726
T(n,k)=Number of length n+3 0..k arrays with no disjoint pairs in any consecutive four terms having the same sum
14
8, 48, 8, 168, 90, 8, 440, 456, 172, 8, 960, 1592, 1248, 334, 8, 1848, 4344, 5796, 3424, 656, 8, 3248, 10098, 19744, 21152, 9392, 1300, 8, 5328, 20816, 55372, 89836, 77236, 25822, 2584, 8, 8280, 39264, 133780, 303924, 408644, 282384, 71060, 5148, 8, 12320
OFFSET
1,1
COMMENTS
Table starts
.8....48.....168......440.......960.......1848........3248.........5328
.8....90.....456.....1592......4344......10098.......20816........39264
.8...172....1248.....5796.....19744......55372......133780.......290004
.8...334....3424....21152.....89836.....303924......860360......2143214
.8...656....9392....77236....408644....1668072.....5532212.....15837692
.8..1300...25822...282384...1859736....9157806....35577396....117045466
.8..2584...71060..1032952...8465936...50284864...228817500....865051288
.8..5148..195536..3779018..38539276..276119316..1471661464...6393427268
.8.10272..537880.13825712.175434372.1516191100..9465023576..47252411120
.8.20520.1480026.50587924.798617096.8325624724.60874728614.349232818280
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = 2*a(n-1) +2*a(n-4) -4*a(n-5)
k=3: [order 27]
k=4: [order 45]
k=5: [order 76]
Empirical for row n:
n=1: a(n) = n^4 + 2*n^3 + 3*n^2 + 2*n
n=2: a(n) = 4*a(n-1) -4*a(n-2) -4*a(n-3) +10*a(n-4) -4*a(n-5) -4*a(n-6) +4*a(n-7) -a(n-8); also a polynomial of degree 5 plus a linear quasipolynomial with period 2
n=3: [order 16; also a polynomial of degree 6 plus a quadratic quasipolynomial with period 12]
n=4: [order 34; also a polynomial of degree 7 plus a cubic quasipolynomial with period 420]
n=5: [order 72]
EXAMPLE
Some solutions for n=4 k=4
..1....0....3....2....4....2....0....1....1....4....1....0....2....3....3....1
..1....1....0....3....3....1....3....0....0....0....1....3....3....3....0....1
..4....1....1....2....0....4....2....4....4....4....0....0....3....0....3....4
..1....4....1....0....0....0....4....1....4....4....3....4....0....2....2....2
..1....3....1....0....4....0....0....1....4....2....0....2....4....4....4....2
..2....3....0....1....2....2....1....0....0....4....4....1....0....4....0....1
..1....1....1....3....3....3....0....1....2....4....3....2....1....3....0....0
CROSSREFS
Sequence in context: A034349 A296797 A024108 * A263506 A216323 A335351
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Sep 23 2014
STATUS
approved