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A203646
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Number of arrays of n 0..15 integers with new values introduced in order 0..15 but otherwise unconstrained.
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3
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1, 2, 5, 15, 52, 203, 877, 4140, 21147, 115975, 678570, 4213597, 27644437, 190899322, 1382958545, 10480142147, 82864869803, 682076806005, 5832742192288, 51724157478221, 474869780161021, 4506714279517080, 44151953491540255
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OFFSET
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1,2
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COMMENTS
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LINKS
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Index entries for linear recurrences with constant coefficients, signature (121, -6685, 223405, -5042947, 81308227, -965408015, 8576039615, -57312583328, 287212533608, -1066335473840, 2866534951280, -5367984964224, 6557974412544, -4622628648960, 1394852659200).
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FORMULA
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Empirical: a(n) = 121*a(n-1) -6685*a(n-2) +223405*a(n-3) -5042947*a(n-4) +81308227*a(n-5) -965408015*a(n-6) +8576039615*a(n-7) -57312583328*a(n-8) +287212533608*a(n-9) -1066335473840*a(n-10) +2866534951280*a(n-11) -5367984964224*a(n-12) +6557974412544*a(n-13) -4622628648960*a(n-14) +1394852659200*a(n-15).
Empirical formula confirmed by extension of first ten columns, see A203641. - Ray Chandler, Jul 06 2024
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CROSSREFS
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KEYWORD
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nonn,changed
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AUTHOR
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STATUS
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approved
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