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 A239859 Number of 2Xn 0..3 arrays with no element equal to zero plus the sum of elements to its left or zero plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4 1
 2, 3, 9, 12, 29, 63, 100, 215, 468, 785, 1654, 3515, 6048, 12676, 26381, 46460, 96810, 198286, 355994, 737992, 1493159, 2724777, 5619409, 11263131, 20836948, 42752798, 85081916, 159218104, 325067366, 643478067, 1215731399, 2470549558, 4871466920 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row 2 of A239858 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = a(n-1) +a(n-2) +7*a(n-3) -8*a(n-4) -7*a(n-5) +9*a(n-7) +10*a(n-8) -24*a(n-9) +5*a(n-10) +29*a(n-11) -18*a(n-12) -10*a(n-13) -10*a(n-14) +16*a(n-15) +12*a(n-16) -12*a(n-17) for n>21 EXAMPLE Some solutions for n=4 ..3..2..3..2....2..3..3..2....2..3..3..3....3..2..2..2....3..2..3..3 ..2..1..1..3....3..1..1..3....3..2..2..2....2..1..0..0....2..3..2..2 CROSSREFS Sequence in context: A067719 A057017 A330242 * A047162 A155929 A175206 Adjacent sequences:  A239856 A239857 A239858 * A239860 A239861 A239862 KEYWORD nonn AUTHOR R. H. Hardin, Mar 28 2014 STATUS approved

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Last modified December 7 09:33 EST 2019. Contains 329843 sequences. (Running on oeis4.)