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 A207611 Triangle of coefficients of polynomials v(n,x) jointly generated with A207610; see Formula section. 3
 1, 2, 1, 3, 2, 1, 5, 4, 2, 1, 8, 8, 5, 2, 1, 13, 15, 11, 6, 2, 1, 21, 28, 23, 14, 7, 2, 1, 34, 51, 47, 32, 17, 8, 2, 1, 55, 92, 93, 70, 42, 20, 9, 2, 1, 89, 164, 181, 148, 97, 53, 23, 10, 2, 1, 144, 290, 346, 306, 217, 128, 65, 26, 11, 2, 1, 233, 509, 653, 619, 472 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Column 1:  Fibonacci numbers, A000045 Column 2:  A029907 Row sums:  A003945 For a discussion and guide to related arrays, see A208510. Subtriangle of the triangle given by (0, 2, -1/2, -1/2, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (1, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 25 2012 LINKS FORMULA u(n,x)=u(n-1,x)+v(n-1,x), v(n,x)=u(n-1,x)+x*v(n-1,x)+1, where u(1,x)=1, v(1,x)=1. T(n,k) = T(n-1,k) + (n-1,k-1) + T(n-2,k) - T(n-2,k-1), T(1,0) = T(2,1) = 1, T(2,0) = 2 and T(n,k) = 0 if k<0 or if k>= n. EXAMPLE First five rows: 1 2...1 3...2...1 5...4...2...1 8...8...5...2...1 (0, 2, -1/2, -1/2, 0, 0, ...) DELTA (1, 0, -1, 1, 0, 0, ...) begins : 1 0, 1 0, 2, 1 0, 3, 2, 1 0, 5, 4, 2, 1 0, 8, 8, 5, 2, 1 0, 13, 15, 11, 6, 2, 1 0, 21, 28, 23, 14, 7, 2, 1 . Philippe Deléham, Mar 25 2012 MATHEMATICA u[1, x_] := 1; v[1, x_] := 1; z = 16; u[n_, x_] := u[n - 1, x] + v[n - 1, x] v[n_, x_] := u[n - 1, x] + x*v[n - 1, x] + 1 Table[Factor[u[n, x]], {n, 1, z}] Table[Factor[v[n, x]], {n, 1, z}] cu = Table[CoefficientList[u[n, x], x], {n, 1, z}]; TableForm[cu] Flatten[%]    (* A207610 *) Table[Expand[v[n, x]], {n, 1, z}] cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; TableForm[cv] Flatten[%]    (* A207611 *) PROG (Python) from sympy import Poly def u(n, x): return 1 if n==1 else u(n - 1, x) + v(n - 1, x) def v(n, x): return 1 if n==1 else u(n - 1, x) + x*v(n - 1, x) + 1 def a(n): return Poly(v(n, x), x).all_coeffs()[::-1] for n in xrange(1, 13): print a(n) # Indranil Ghosh, May 28 2017 CROSSREFS Cf. A207610, A208510. Sequence in context: A322083 A058399 A209434 * A320973 A058400 A131344 Adjacent sequences:  A207608 A207609 A207610 * A207612 A207613 A207614 KEYWORD nonn,tabl AUTHOR Clark Kimberling, Feb 19 2012 STATUS approved

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Last modified October 15 07:56 EDT 2019. Contains 328026 sequences. (Running on oeis4.)