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A190042 Number of nondecreasing arrangements of 5 numbers in 0..n with the last equal to n and each after the second equal to the sum of one or two of the preceding three. 1
2, 8, 10, 18, 16, 30, 22, 40, 31, 49, 36, 64, 41, 71, 53, 81, 55, 97, 61, 103, 74, 112, 75, 131, 80, 134, 96, 144, 94, 164, 100, 166, 117, 175, 114, 198, 119, 197, 139, 207, 133, 231, 139, 229, 160, 238, 153, 265, 158, 260, 182, 270, 172, 298, 178, 292, 203, 301, 192 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 3 of A190041.

LINKS

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

FORMULA

Empirical: a(n) = -2*a(n-1) -2*a(n-2) +3*a(n-4) +4*a(n-5) +3*a(n-6) -2*a(n-8) -2*a(n-9) -a(n-10).

Empirical g.f.: x*(2 + 12*x + 30*x^2 + 54*x^3 + 66*x^4 + 66*x^5 + 46*x^6 + 26*x^7 + 9*x^8 + 3*x^9) / ((1 - x)^2*(1 + x)^2*(1 + x^2)*(1 + x + x^2)^2). - Colin Barker, May 04 2018

EXAMPLE

All solutions for n=3:

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

..1....1....3....3....3....2....2....1....3....1

..1....2....3....3....3....3....2....1....3....2

..2....2....3....3....3....3....3....2....3....3

..3....3....3....3....3....3....3....3....3....3

CROSSREFS

Cf. A190041.

Sequence in context: A226831 A197115 A288824 * A297293 A294157 A082396

Adjacent sequences:  A190039 A190040 A190041 * A190043 A190044 A190045

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 04 2011

STATUS

approved

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Last modified August 5 18:00 EDT 2021. Contains 346488 sequences. (Running on oeis4.)