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A240790
Number of n X 3 0..3 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of elements above it or zero plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4.
1
4, 5, 8, 27, 49, 50, 89, 115, 182, 289, 425, 651, 992, 1486, 2255, 3349, 5040, 7706, 11754, 17525, 26365, 39661, 59893, 89903, 135336, 203491, 306233, 460867, 692971, 1040765, 1565790, 2353754, 3540545, 5319995, 8000324, 12027862, 18084789
OFFSET
1,1
COMMENTS
Column 3 of A240792.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-5) +4*a(n-6) +a(n-7) +4*a(n-8) +5*a(n-9) -6*a(n-10) -12*a(n-11) -a(n-12) -13*a(n-13) -16*a(n-14) -7*a(n-15) +13*a(n-16) +2*a(n-17) +20*a(n-18) +24*a(n-19) +15*a(n-20) -3*a(n-21) -2*a(n-22) -20*a(n-23) -44*a(n-24) -11*a(n-25) +9*a(n-26) -82*a(n-27) -30*a(n-28) +19*a(n-29) -21*a(n-30) -108*a(n-31) +132*a(n-32) +43*a(n-33) -68*a(n-34) +17*a(n-35) +171*a(n-36) -171*a(n-37) +66*a(n-38) +206*a(n-39) -46*a(n-40) -124*a(n-41) +214*a(n-42) -29*a(n-43) -283*a(n-44) +123*a(n-45) +129*a(n-46) -251*a(n-47) -6*a(n-48) +164*a(n-49) -17*a(n-50) -121*a(n-51) +216*a(n-52) +51*a(n-53) -79*a(n-54) +40*a(n-55) +58*a(n-56) -21*a(n-57) -16*a(n-58) +32*a(n-59) -3*a(n-60) -47*a(n-61) -29*a(n-62) -9*a(n-63) -2*a(n-64) -11*a(n-65) -2*a(n-66) +10*a(n-67) -6*a(n-69) +12*a(n-70) +3*a(n-71) -4*a(n-72) -3*a(n-73) +3*a(n-74) +a(n-75) -3*a(n-76) for n>87.
EXAMPLE
Some solutions for n=4:
..3..2..3....3..2..3....3..2..3....3..2..3....3..2..3....3..2..3....3..2..3
..3..2..3....3..1..3....3..1..3....3..2..3....3..2..1....3..2..1....3..2..3
..2..2..2....2..1..1....2..2..2....2..2..2....2..0..2....2..2..3....2..2..2
..2..0..2....2..0..1....3..1..3....3..1..3....2..0..1....2..0..2....2..1..2
CROSSREFS
Cf. A240792.
Sequence in context: A226795 A113726 A207191 * A229861 A140315 A055497
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 12 2014
STATUS
approved