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A190044 Number of nondecreasing arrangements of 7 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, 12, 18, 39, 33, 72, 43, 105, 69, 123, 72, 190, 83, 169, 151, 217, 108, 276, 120, 297, 206, 261, 150, 427, 179, 318, 259, 405, 185, 509, 201, 452, 326, 413, 277, 652, 228, 470, 383, 626, 263, 688, 276, 631, 501, 559, 303, 893, 323, 673, 509, 748, 341, 883, 418, 831 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 5 of A190041

LINKS

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

FORMULA

Empirical: a(n) = -4*a(n-1) -13*a(n-2) -33*a(n-3) -75*a(n-4) -152*a(n-5) -286*a(n-6) -500*a(n-7) -826*a(n-8) -1292*a(n-9) -1929*a(n-10) -2753*a(n-11) -3772*a(n-12) -4965*a(n-13) -6291*a(n-14) -7671*a(n-15) -9002*a(n-16) -10148*a(n-17) -10961*a(n-18) -11284*a(n-19) -10976*a(n-20) -9925*a(n-21) -8069*a(n-22) -5411*a(n-23) -2025*a(n-24) +1935*a(n-25) +6252*a(n-26) +10648*a(n-27) +14823*a(n-28) +18464*a(n-29) +21297*a(n-30) +23091*a(n-31) +23708*a(n-32) +23091*a(n-33) +21297*a(n-34) +18464*a(n-35) +14823*a(n-36) +10648*a(n-37) +6252*a(n-38) +1935*a(n-39) -2025*a(n-40) -5411*a(n-41) -8069*a(n-42) -9925*a(n-43) -10976*a(n-44) -11284*a(n-45) -10961*a(n-46) -10148*a(n-47) -9002*a(n-48) -7671*a(n-49) -6291*a(n-50) -4965*a(n-51) -3772*a(n-52) -2753*a(n-53) -1929*a(n-54) -1292*a(n-55) -826*a(n-56) -500*a(n-57) -286*a(n-58) -152*a(n-59) -75*a(n-60) -33*a(n-61) -13*a(n-62) -4*a(n-63) -a(n-64)

EXAMPLE

Some solutions for n=3

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A257256 A325767 A335799 * A066238 A101074 A115109

Adjacent sequences:  A190041 A190042 A190043 * A190045 A190046 A190047

KEYWORD

nonn

AUTHOR

R. H. Hardin May 04 2011

STATUS

approved

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Last modified August 3 01:36 EDT 2021. Contains 346429 sequences. (Running on oeis4.)