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A228741 Number of arrays of the median of three adjacent elements of some length-6 0..n array. 1
16, 77, 232, 545, 1096, 1981, 3312, 5217, 7840, 11341, 15896, 21697, 28952, 37885, 48736, 61761, 77232, 95437, 116680, 141281, 169576, 201917, 238672, 280225, 326976, 379341, 437752, 502657, 574520, 653821, 741056, 836737, 941392, 1055565 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = (n+1)*(2*n^3+10*n^2+9*n+3)/3.
Empirical: G.f. -x*(16-3*x+7*x^2-5*x^3+x^4) / (x-1)^5 . - R. J. Mathar, Sep 02 2013
EXAMPLE
Some solutions for n = 4:
..3..3..0..4..0..2..2..2..1..3..0..1..1..0..0..2
..2..0..3..0..0..2..4..4..1..2..3..3..0..0..2..4
..1..0..1..0..3..3..3..0..2..0..3..3..3..4..2..2
..2..1..3..0..1..2..4..2..0..1..4..3..4..2..4..0
CROSSREFS
Row 4 of A228740.
Sequence in context: A253691 A300919 A007834 * A346636 A200873 A082966
KEYWORD
nonn
AUTHOR
R. H. Hardin, Sep 01 2013
STATUS
approved

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Last modified April 21 06:29 EDT 2024. Contains 371850 sequences. (Running on oeis4.)