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EXAMPLE
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O.g.f.: A(x) = 1 + x + 9*x^2 + 179*x^3 + 5661*x^4 + 249424*x^5 + 14337039*x^6 + 1035838044*x^7 + 91867414241*x^8 + 9833503227827*x^9 + ...
ILLUSTRATION OF DEFINITION.
The table of coefficients of x^k/k! in exp( n^2 * x*A(x) ) / A(x) begins:
n=0: [1, -1, -16, -972, -125952, -28275000, -9885939840, ...];
n=1: [1, 0, -15, -968, -125835, -28263864, -9883855835, ...];
n=2: [1, 3, 0, -860, -123456, -28073976, -9850185728, ...];
n=3: [1, 8, 65, 0, -104811, -26970576, -9680119083, ...];
n=4: [1, 15, 240, 3892, 0, -21937464, -9078485120, ...];
n=5: [1, 24, 609, 16528, 457173, 0, -7077136715, ...];
n=6: [1, 35, 1280, 49572, 2066880, 89033736, 0, ...];
n=7: [1, 48, 2385, 123880, 6839349, 411165624, 26124539077, 0, ...]; ...
in which the main diagonal is all zeros after the initial term, illustrating that [x^n] exp( n^2 * x*A(x) ) / A(x) = 0 for n > 0.
Terms along the secondary diagonal in the above table are divisible by the odd numbers: [1, 3/3, 65/5, 3892/7, 457173/9, 89033736/11, 26124539077/13, ...] = [1, 1, 13, 556, 50797, 8093976, 2009579929, ...].
RELATED SERIES.
exp( x*A(x) ) = 1 + x + 3*x^2/2! + 61*x^3/3! + 4537*x^4/4! + 702501*x^5/5! + 183891571*x^6/6! + 73567995313*x^7/7! + 42361186187601*x^8/8! + ...
The arithmetic inverse of the o.g.f. begins:
1/A(x) = 1 - x - 8*x^2 - 162*x^3 - 5248*x^4 - 235625*x^5 - 13730472*x^6 - 1001798042*x^7 - 89479215104*x^8 - 9627430506669*x^9 + ...
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