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 A269584 Number of length-4 0..n arrays with no repeated value differing from the previous repeated value by more than one. 1
 16, 79, 250, 613, 1276, 2371, 4054, 6505, 9928, 14551, 20626, 28429, 38260, 50443, 65326, 83281, 104704, 130015, 159658, 194101, 233836, 279379, 331270, 390073, 456376, 530791, 613954, 706525, 809188, 922651, 1047646, 1184929, 1335280 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = n^4 + 4*n^3 + 5*n^2 + 5*n + 1. Conjectures from Colin Barker, Jan 24 2019: (Start) G.f.: x*(16 - x + 15*x^2 - 7*x^3 + x^4) / (1 - x)^5. a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5. (End) EXAMPLE Some solutions for n=6: ..4. .0. .1. .6. .0. .1. .1. .2. .1. .3. .5. .1. .2. .3. .0. .6 ..0. .5. .3. .4. .3. .5. .2. .1. .2. .2. .2. .3. .5. .4. .6. .2 ..1. .6. .0. .1. .6. .4. .1. .1. .5. .6. .4. .1. .3. .0. .2. .2 ..2. .6. .4. .0. .4. .1. .5. .0. .0. .0. .3. .0. .2. .5. .2. .0 CROSSREFS Row 4 of A269583. Sequence in context: A250231 A212896 A250279 * A044203 A044584 A111732 Adjacent sequences: A269581 A269582 A269583 * A269585 A269586 A269587 KEYWORD nonn AUTHOR R. H. Hardin, Mar 01 2016 STATUS approved

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Last modified October 3 14:07 EDT 2023. Contains 365866 sequences. (Running on oeis4.)