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A248465 Number of length 4+2 0..n arrays with no three consecutive terms having the sum of any two elements equal to twice the third 1
26, 144, 1436, 6040, 21182, 56782, 138534, 295078, 589916, 1082878, 1900666, 3161064, 5083368, 7857546, 11844802, 17344202, 24892396, 34927864, 48224830, 65403924, 87536430, 115449764, 150581308, 194049230, 247712034, 312987618 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A248461

LINKS

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

FORMULA

Empirical: a(n) = -a(n-1) -a(n-2) +2*a(n-5) +3*a(n-6) +4*a(n-7) +3*a(n-8) +2*a(n-9) -3*a(n-11) -4*a(n-12) -6*a(n-13) -5*a(n-14) -5*a(n-15) +3*a(n-18) +2*a(n-19) +4*a(n-20) +a(n-21) -a(n-23) +2*a(n-25) +2*a(n-26) +5*a(n-27) +3*a(n-28) +5*a(n-29) -5*a(n-32) -3*a(n-33) -5*a(n-34) -2*a(n-35) -2*a(n-36) +a(n-38) -a(n-40) -4*a(n-41) -2*a(n-42) -3*a(n-43) +5*a(n-46) +5*a(n-47) +6*a(n-48) +4*a(n-49) +3*a(n-50) -2*a(n-52) -3*a(n-53) -4*a(n-54) -3*a(n-55) -2*a(n-56) +a(n-59) +a(n-60) +a(n-61)

EXAMPLE

Some solutions for n=6

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

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

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

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

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

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

CROSSREFS

Sequence in context: A331458 A238917 A200449 * A014552 A192289 A230906

Adjacent sequences: A248462 A248463 A248464 * A248466 A248467 A248468

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 06 2014

STATUS

approved

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Last modified December 1 18:55 EST 2022. Contains 358475 sequences. (Running on oeis4.)