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A208896
Rectangular table where the g.f. of row n satisfies: R(n,x) = 1 + x*R(n,x)^n * [d/dx x/R(n,x)] for n>=0, as read by antidiagonals.
3
1, 1, 1, 1, 1, -2, 1, 1, -1, 9, 1, 1, 0, 3, -56, 1, 1, 1, 0, -13, 425, 1, 1, 2, 0, 0, 71, -3726, 1, 1, 3, 3, -1, 0, -461, 36652, 1, 1, 4, 9, 0, 1, 0, 3447, -397440, 1, 1, 5, 18, 19, -12, 0, 0, -29093, 4695489, 1, 1, 6, 30, 72, 0, -14, 0, 0, 273343, -59941550
OFFSET
0,6
COMMENTS
The following property accounts for the zeros along the main diagonal.
The row g.f.s satisfy: [x^k] R(n,x)^(k-n+1) = [x^k] R(n,x)^(k-n) for k>=2
and thus when k=n we have [x^n] R(n,x) = [x^n] R(n,x)^0 = 0 for n>=2.
LINKS
EXAMPLE
Coefficients in the n-th row g.f., R(n,x), of this table begins:
n=0: [1, 1,-2, 9, -56, 425, -3726, 36652, -397440, 4695489, ...];
n=1: [1, 1,-1, 3, -13, 71, -461, 3447, -29093, 273343, ...];
n=2: [1, 1, 0, 0, 0, 0, 0, 0, 0, 0, ...];
n=3: [1, 1, 1, 0, -1, 1, 0, 0, -5, 27, ...];
n=4: [1, 1, 2, 3, 0, -12, -14, 43, 96, -50, ...];
n=5: [1, 1, 3, 9, 19, 0, -195, -732, -453, 6495, ...];
n=6: [1, 1, 4, 18, 72, 201, 0, -4200, -27984, -91044, ...];
n=7: [1, 1, 5, 30, 175, 880, 3106, 0, -114485,-1124735, ...];
n=8: [1, 1, 6, 45, 344, 2451, 14946, 64522, 0,-3805692, ...];
n=9: [1, 1, 7, 63, 595, 5453, 45927, 331177, 1704795, 0, ...];
n=10:[1, 1, 8, 84, 944,10550,112336,1094604, 9157984,55095601, 0,...]; ...
in which the main diagonal is zeros for n>=2.
Initial row g.f.s are illustrated by the following.
R(0,x) = 1 + x*[d/dx x/R(0,x)] begins:
R(0,x) = 1 + x - 2*x^2 + 9*x^3 - 56*x^4 + 425*x^5 - 3726*x^6 +...
which satisfies: [x^k] R(0,x)^(k+1) = [x^k] R(0,x)^k for k>=2.
...
R(1,x) = 1 + x*R(1,x)*[d/dx x/R(1,x)] begins:
R(1,x) = 1 + x - x^2 + 3*x^3 - 13*x^4 + 71*x^5 - 461*x^6 + 3447*x^7 +...
which satisfies: [x^k] R(1,x)^k = [x^k] R(1,x)^(k-1) for k>=2.
...
R(2,x) = 1 + x*R(2,x)^2*[d/dx x/R(2,x)] is satisfied by:
R(2,x) = 1 + x,
which satisfies: [x^k] R(2,x)^(k-1) = [x^k] R(2,x)^(k-2) = 0 for k>=2.
...
R(3,x) = 1 + x*R(3,x)^3*[d/dx x/R(3,x)] begins:
R(3,x) = 1 + x + x^2 - x^4 + x^5 - 5*x^8 + 27*x^9 - 147*x^10 + 996*x^11 +...
which satisfies: [x^k] R(3,x)^(k-2) = [x^k] R(3,x)^(k-3) for k>=2.
...
PROG
(PARI) {T(n, k)=local(ROWn=1+x+x*O(x^k)); for(i=0, k, ROWn=1+x*ROWn^n*deriv(x/ROWn)); polcoeff(ROWn, k)}
for(n=0, 12, for(k=0, 12, print1(T(n, k), ", ")); print(""))
CROSSREFS
Cf. A158883 (row 0), A158882 (row 1), A208897, A208898.
Sequence in context: A264081 A061538 A123602 * A288972 A065521 A225700
KEYWORD
sign,tabl
AUTHOR
Paul D. Hanna, Mar 03 2012
STATUS
approved