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 A214541 Number of 3X3X3 triangular 0..n arrays with no element lying outside the (possibly reversed) range delimited by its sw and se neighbors, and every horizontal row having the same average value 1
 2, 15, 38, 79, 152, 263, 418, 643, 942, 1329, 1832, 2463, 3234, 4185, 5326, 6677, 8280, 10153, 12314, 14817, 17678, 20923, 24608, 28757, 33394, 38587, 44358, 50739, 57800, 65571, 74082, 83415, 93598, 104669, 116712, 129763, 143858, 159093, 175502 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row 3 of A214540 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 2*a(n-1) -3*a(n-4) +3*a(n-6) -2*a(n-9) +a(n-10). Empirical: G.f. -x*(2+11*x+8*x^2+3*x^3+4*x^5-x^7-2*x^8+x^9) / ( (1+x)*(1+x+x^2)^2*(x-1)^5 ). - R. J. Mathar, Jul 23 2012 EXAMPLE Some solutions for n=4 ....3......2......3......2......3......3......1......0......2......2......1 ...2.4....3.1....4.2....3.1....3.3....3.3....1.1....0.0....3.1....2.2....0.2 ..4.1.4..3.3.0..4.1.4..2.4.0..3.2.4..3.3.3..1.1.1..0.0.0..3.1.2..1.3.2..0.1.2 CROSSREFS Sequence in context: A064113 A007217 A295367 * A180223 A070009 A070170 Adjacent sequences:  A214538 A214539 A214540 * A214542 A214543 A214544 KEYWORD nonn AUTHOR R. H. Hardin Jul 20 2012 STATUS approved

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Last modified May 10 15:42 EDT 2021. Contains 343775 sequences. (Running on oeis4.)