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A264552
Number of (3+1)X(n+1) arrays of permutations of 0..n*4+3 with each element having directed index change -1,1 -1,2 1,0 or 0,-1.
1
0, 5, 16, 36, 172, 764, 2728, 9880, 38818, 150536, 567680, 2152907, 8249172, 31505782, 119890865, 456906182, 1743546208, 6648727988, 25342679205, 96627142521, 368474752553, 1404944654910, 5356632127953, 20424348993729
OFFSET
1,2
COMMENTS
Row 3 of A264550.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +a(n-2) +4*a(n-3) +41*a(n-4) -104*a(n-5) +14*a(n-6) +167*a(n-7) -715*a(n-8) +1169*a(n-9) -1018*a(n-10) -3680*a(n-11) +8691*a(n-12) -10335*a(n-13) +2525*a(n-14) +35277*a(n-15) -50582*a(n-16) +64373*a(n-17) +11060*a(n-18) -207508*a(n-19) +200293*a(n-20) -204582*a(n-21) -124748*a(n-22) +704108*a(n-23) -499827*a(n-24) +365700*a(n-25) +473743*a(n-26) -1541579*a(n-27) +729138*a(n-28) -331526*a(n-29) -929717*a(n-30) +2313138*a(n-31) -591289*a(n-32) +10149*a(n-33) +1058138*a(n-34) -2448606*a(n-35) +225766*a(n-36) +341725*a(n-37) -740229*a(n-38) +1867654*a(n-39) -9921*a(n-40) -441602*a(n-41) +343946*a(n-42) -1047499*a(n-43) -9489*a(n-44) +322880*a(n-45) -125643*a(n-46) +431100*a(n-47) -8968*a(n-48) -160742*a(n-49) +44437*a(n-50) -124400*a(n-51) +6980*a(n-52) +54449*a(n-53) -13758*a(n-54) +23185*a(n-55) -1859*a(n-56) -11695*a(n-57) +2887*a(n-58) -2532*a(n-59) +298*a(n-60) +1457*a(n-61) -383*a(n-62) +155*a(n-63) -26*a(n-64) -100*a(n-65) +29*a(n-66) -4*a(n-67) +a(n-68) +3*a(n-69) -a(n-70)
EXAMPLE
Some solutions for n=4
..1..2..6..4..8....1..2..3..4..7....1..2..3..6..7....1..2..6..4..8
..0..7.10..3.12....0.10..8..9.13....0.10..8..9..4....0..7.11..3.12
..5.15.13.17..9....5..6.15.17.18....5.15.13.17.18....5.15.13.16..9
.16.11.18.19.14...16.11.12.19.14...16.11.12.19.14...10.17.18.19.14
CROSSREFS
Cf. A264550.
Sequence in context: A055232 A211806 A001210 * A128848 A274248 A188427
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 17 2015
STATUS
approved