A213458 Number of 0..3 arrays of length n+3 with sum less than 6 in any length 4 subsequence (=less than 50% duty cycle)

106, 310, 927, 2735, 7803, 22506, 65425, 190318, 551598, 1597812, 4632940, 13439852, 38977905, 113018097, 327714656, 950345164, 2755932228, 7991769082, 23174685375, 67202984107, 194879111652, 565120621828, 1638762823886

Offset

1,1

Comments

Column 2 of A213464

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +a(n-2) +a(n-3) +16*a(n-4) -8*a(n-5) -13*a(n-6) -8*a(n-7) -64*a(n-8) +15*a(n-9) +37*a(n-10) +25*a(n-11) +136*a(n-12) -54*a(n-13) -36*a(n-14) -34*a(n-15) -173*a(n-16) +107*a(n-17) +19*a(n-18) +14*a(n-19) +144*a(n-20) -129*a(n-21) +4*a(n-22) +12*a(n-23) -103*a(n-24) +98*a(n-25) -18*a(n-26) -15*a(n-27) +75*a(n-28) -39*a(n-29) +18*a(n-30) +6*a(n-31) -40*a(n-32) +9*a(n-33) -8*a(n-34) -a(n-35) +11*a(n-36) -a(n-37) +a(n-38) -a(n-40)

Example

Some solutions for n=3
..0....2....0....1....2....1....0....1....2....1....3....1....1....0....1....0
..0....0....3....0....1....2....0....0....1....2....0....0....1....0....0....0
..0....3....1....0....0....1....0....0....2....2....2....1....1....0....0....1
..0....0....1....0....1....0....2....1....0....0....0....2....1....1....1....0
..1....0....0....0....1....0....0....1....1....1....0....0....2....0....2....1
..3....2....0....3....0....3....0....0....2....2....0....0....1....2....0....0

Crossrefs

Sequence in context: A260202 A255818 A090775 * A260937 A200868 A234421

Adjacent sequences: A213455 A213456 A213457 * A213459 A213460 A213461

Keyword

nonn

Author

R. H. Hardin Jun 12 2012

Status

approved