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 A143411 Square array, read by antidiagonals: form the Euler-Seidel matrix for the sequence {2^k*k!} and then divide column k by 2^k*k!. 4
 1, 3, 1, 13, 5, 1, 79, 33, 7, 1, 633, 277, 61, 9, 1, 6331, 2849, 643, 97, 11, 1, 75973, 34821, 7993, 1225, 141, 13, 1, 1063623, 493825, 114751, 17793, 2071, 193, 15, 1, 17017969, 7977173, 1870837, 292681, 34361, 3229, 253, 17, 1, 306323443 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS This table is closely connected to the constant 1/sqrt(e). The row, column and diagonal entries of this table occur in series acceleration formulas for 1/sqrt(e). For a similar table based on the differences of the sequence {2^k*k!} and related to the constant sqrt(e), see A143410. For other arrays similarly related to constants see A086764 (for e), A143409 (for 1/e), A008288 (for log(2)), A108625 (for zeta(2)) and A143007 (for zeta(3)). LINKS D. Dumont, Matrices d'Euler-Seidel, Sem. Loth. Comb. B05c (1981) 59-78. Eric Weisstein's World of Mathematics Poisson-Charlier polynomial FORMULA T(n,k) = 1/k!*Sum_{j = 0..n} 2^j*binomial(n,j)*(k+j)!. Relation with Poisson-Charlier polynomials c_n(x,a): T(n,k) = (-1)^n*c_n(-(k+1),1/2). Recurrence relations: T(n,k) = 2*n*T(n-1,k) + T(n,k-1); T(n,k) = 2*(n+k)*T(n-1,k) + T(n-1,k-1); T(n,k) = 2*(k+1)*T(n-1,k+1) + T(n-1,k). Recurrence for row n entries: 2*k*T(n,k) = (2*n+2*k-1)*T(n,k-1) + T(n,k-2). E.g.f. for column k: exp(y)/(1 - 2*y)^(k+1). E.g.f. for array: exp(y)/(1 - x - 2*y) = (1 + x + x^2 + ...) + (3 + 5*x + 7*x^2 + ...)*y + (13 + 37*x + 61*x^2 + ...)*y^2/2! + ... . Series acceleration formulas for 1/sqrt(e): Row n: 1/sqrt(e) = 2^n*n!*(1/T(n,0) - 1/(2*1!*T(n,0)*T(n,1)) + 1/(2^2*2!*T(n,1)*T(n,2)) - 1/(2^3*3!*T(n,2)*T(n,3)) + ...). For example, row 3 gives 1/sqrt(e) = 48*(1/79 - 1/(2*79*277) + 1/(8*277*643) - 1/(48*643*1225) + ...). Column k: 1/sqrt(e) = (1 - (1/2)/1! + (1/2)^2/2! - ... + (-1/2)^k/k!) + (-1)^(k+1)/(2^k*k!)*( Sum_{n = 0..inf} 2^n*n!/(T(n,k)*T(n+1,k)) ). For example, column 3 gives 1/sqrt(e) = 29/48 + 1/48*( 1/(1*9) + 2/(9*97) + 8/(97*1225) + 48/(1225*17793) + ... ). Main diagonal: 1/sqrt(e) = 1 - 2*( 1/(1*5) - 1/(5*61) + 1/(61*1225) - ... ). See A065919. EXAMPLE The Euler-Seidel matrix for the sequence {2^k*k!} begins ======================================== n\k|.....0.....1.....2.....3.....4.....5 ======================================== 0..|.....1.....2.....8....48...384..3840 1..|.....3....10....56...432..4224 2..|....13....66...488..4656 3..|....79...554..5144 4..|...633..5698 5..|..6331 6..|.. ... Dividing the k-th column by 2^k*k! gives ======================================== n\k|.....0.....1.....2.....3.....4.....5 ======================================== 0..|.....1.....1.....1.....1.....1.....1... 1..|.....3.....5.....7.....9....11 2..|....13....33....61....97 3..|....79...277...643 4..|...633..2849 5..|..6331 6..|.. MAPLE with combinat: T := (n, k) -> 1/k!*add(2^j*binomial(n, j)*(k+j)!, j = 0..n): for n from 0 to 9 do seq(T(n, k), k = 0..9) end do; CROSSREFS Cf. A008288, A065919 (main diagonal), A076571, A086764, A108625, A143007, A143409, A143410. Sequence in context: A322384 A113139 A266577 * A096773 A118384 A258239 Adjacent sequences:  A143408 A143409 A143410 * A143412 A143413 A143414 KEYWORD easy,nonn,tabl AUTHOR Peter Bala, Aug 19 2008 STATUS approved

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Last modified October 16 08:15 EDT 2019. Contains 328051 sequences. (Running on oeis4.)