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 A298432 a(n) = Sum_{k=0..n-1} T(n-k, k+1) where T(n, k) is the number of tight n X k pavings (defined in A285357). 1
 1, 2, 6, 24, 118, 680, 4456, 32512, 260080, 2254464, 20982768, 208142912, 2187336048, 24229170560 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS D. E. Knuth (Proposer), Tight m-by-n pavings; Problem 12005, Amer. Math. Monthly 124 (No. 8, Oct. 2017), page 755. D. E. Knuth, A conjecture that had to be true, Stanford Lecture: Don Knuth's Christmas Tree Lecture 2017. EXAMPLE These are the row sums of A285357 if A285357 is written as a triangle: 1; 1,   1; 1,   4,     1; 1,  11,    11,     1; 1,  26,    64,    26,      1; 1,  57,   282,   282,     57,     1; 1, 120,  1071,  2072,   1071,   120,     1; 1, 247,  3729, 12279,  12279,  3729,   247,   1; 1, 502, 12310, 63858, 106738, 63858, 12310, 502, 1; CROSSREFS Cf. A000295, A285357, A285361, A298362. Sequence in context: A263777 A088713 A193938 * A336072 A328501 A328442 Adjacent sequences:  A298429 A298430 A298431 * A298433 A298434 A298435 KEYWORD nonn,more AUTHOR Peter Luschny, Jan 19 2018 EXTENSIONS a(11) from Hugo Pfoertner, Jan 19 2018 a(12)-a(14) from Denis Roegel, Feb 24 2018 STATUS approved

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Last modified June 19 00:04 EDT 2021. Contains 345125 sequences. (Running on oeis4.)