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A255812
Rectangular array: row n gives the denominators in the positive convolutory n-th root of (1,1,1,...).
2
1, 1, 1, 1, 2, 1, 1, 8, 3, 1, 1, 16, 9, 4, 1, 1, 128, 81, 32, 5, 1, 1, 256, 243, 128, 25, 6, 1, 1, 1024, 729, 2048, 125, 72, 7, 1, 1, 2048, 6561, 8192, 625, 1296, 49, 8, 1, 1, 32768, 19683, 65536, 15625, 31104, 343, 128, 9, 1, 1, 65536, 59049, 262144, 78125
OFFSET
1,5
COMMENTS
(See Comments at A255811.)
LINKS
FORMULA
G.f. of s: (1 - t)^(-1/n).
EXAMPLE
First, regarding the numbers numerator/denominator, we have
row 1: 1,1,1,1,1,1,1,1,1,1,1,1,..., the 0th self-convolution of (1,1,1,...);
row 2: 1,1/2,3/8,5/16,35/128,63/256, ..., convolutory sqrt of (1,1,1,...);
row 3: 1,1/3,2/9,14/81,35/243,91/729,..., convolutory 3rd root
row 4: 1,1/4,5/32,15/128,195/2048,663/8192,..., convolutory 4th root.
Taking only denominators:
row 1: 1,1,1,1,1,1,1,...
row 2: 1,2,8,16,128,...
row 3: 1,3,9,81,243,729,...
row 4: 1,4,32,128,2048,8192,...
MATHEMATICA
z = 15; t[n_] := CoefficientList[Normal[Series[(1 - t)^(-1/n), {t, 0, z}]], t];
u = Table[Numerator[t[n]], {n, 1, z}]
TableForm[Table[u[[n, k]], {n, 1, z}, {k, 1, z}]] (*A255811 array*)
Table[u[[n - k + 1, k]], {n, z}, {k, n, 1, -1}] // Flatten (*A255811 sequence*)
v = Table[Denominator[t[n]], {n, 1, z}]
TableForm[Table[v[[n, k]], {n, 1, z}, {k, 1, z}]] (*A255812 array*)
Table[v[[n - k + 1, k]], {n, z}, {k, n, 1, -1}] // Flatten (*A255812 sequence*)
CROSSREFS
Sequence in context: A077058 A053373 A297733 * A249141 A353953 A102875
KEYWORD
nonn,easy,tabl,frac
AUTHOR
Clark Kimberling, Mar 11 2015
STATUS
approved