A189330 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 four

2, 12, 22, 49, 54, 110, 91, 179, 154, 238, 190, 360, 215, 376, 333, 453, 290, 604, 334, 607, 478, 634, 411, 904, 428, 771, 658, 882, 504, 1132, 537, 1023, 832, 1023, 627, 1453, 625, 1158, 1007, 1336, 710, 1614, 753, 1459, 1191, 1398, 825, 2016, 831, 1574, 1337

Offset

1,1

Comments

Row 5 of A189326

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) -76*a(n-4) -156*a(n-5) -300*a(n-6) -538*a(n-7) -919*a(n-8) -1494*a(n-9) -2337*a(n-10) -3518*a(n-11) -5129*a(n-12) -7245*a(n-13) -9954*a(n-14) -13307*a(n-15) -17352*a(n-16) -22075*a(n-17) -27440*a(n-18) -33327*a(n-19) -39579*a(n-20) -45945*a(n-21) -52136*a(n-22) -57780*a(n-23) -62486*a(n-24) -65817*a(n-25) -67357*a(n-26) -66703*a(n-27) -63526*a(n-28) -57579*a(n-29) -48739*a(n-30) -37025*a(n-31) -22608*a(n-32) -5832*a(n-33) +12817*a(n-34) +32691*a(n-35) +53055*a(n-36) +73066*a(n-37) +91885*a(n-38) +108650*a(n-39) +122610*a(n-40) +133081*a(n-41) +139585*a(n-42) +141780*a(n-43) +139585*a(n-44) +133081*a(n-45) +122610*a(n-46) +108650*a(n-47) +91885*a(n-48) +73066*a(n-49) +53055*a(n-50) +32691*a(n-51) +12817*a(n-52) -5832*a(n-53) -22608*a(n-54) -37025*a(n-55) -48739*a(n-56) -57579*a(n-57) -63526*a(n-58) -66703*a(n-59) -67357*a(n-60) -65817*a(n-61) -62486*a(n-62) -57780*a(n-63) -52136*a(n-64) -45945*a(n-65) -39579*a(n-66) -33327*a(n-67) -27440*a(n-68) -22075*a(n-69) -17352*a(n-70) -13307*a(n-71) -9954*a(n-72) -7245*a(n-73) -5129*a(n-74) -3518*a(n-75) -2337*a(n-76) -1494*a(n-77) -919*a(n-78) -538*a(n-79) -300*a(n-80) -156*a(n-81) -76*a(n-82) -33*a(n-83) -13*a(n-84) -4*a(n-85) -a(n-86)

Example

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

Crossrefs

Sequence in context: A017293 A367294 A244188 * A120672 A190642 A108960

Adjacent sequences: A189327 A189328 A189329 * A189331 A189332 A189333

Keyword

nonn

Author

R. H. Hardin Apr 20 2011

Status

approved