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A109626 Consider the array T(n, m) where the n-th row is the sequence of integer coefficients of A(x), where 1<=a(n)<=n, such that A(x)^(1/n) consists entirely of integer coefficients and where m is the (m+1)-th coefficient. This is the antidiagonal read from lower left to upper right. 25
1, 1, 1, 1, 2, 1, 1, 3, 1, 1, 1, 4, 3, 2, 1, 1, 5, 2, 1, 2, 1, 1, 6, 5, 4, 3, 2, 1, 1, 7, 3, 5, 3, 3, 1, 1, 1, 8, 7, 2, 5, 4, 3, 2, 1, 1, 9, 4, 7, 3, 1, 4, 3, 2, 1, 1, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 1, 11, 5, 3, 2, 7, 6, 5, 1, 3, 1, 1, 1, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 1, 13, 6, 11, 10, 9, 4, 1, 3, 5 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,5

EXAMPLE

Table begins

\k...0...1....2....3....4....5....6....7....8....9...10...11...12...13

n\

1| 1 1 1 1 1 1 1 1 1 1 1 1 1 1

2| 1 2 1 2 2 2 1 2 2 2 1 2 1 2

3| 1 3 3 1 3 3 3 3 3 3 3 3 1 3

4| 1 4 2 4 3 4 4 4 1 4 4 4 3 4

5| 1 5 5 5 5 1 5 5 5 5 4 5 5 5

6| 1 6 3 2 3 6 6 6 3 4 6 6 6 6

7| 1 7 7 7 7 7 7 1 7 7 7 7 7 7

8| 1 8 4 8 2 8 4 8 7 8 8 8 4 8

9| 1 9 9 3 9 9 3 9 9 1 9 9 6 9

10| 1 10 5 10 10 2 5 10 10 10 3 10 5 10

11| 1 11 11 11 11 11 11 11 11 11 11 1 11 11

12| 1 12 6 4 9 12 4 12 12 8 6 12 6 12

13| 1 13 13 13 13 13 13 13 13 13 13 13 13 1

14| 1 14 7 14 7 14 14 2 7 14 14 14 14 14

15| 1 15 15 5 15 3 10 15 15 10 15 15 5 15

16| 1 16 8 16 4 16 8 16 10 16 8 16 12 16

MATHEMATICA

f[n_] := f[n] = Block[{a}, a[0] = 1; a[l_] := a[l] = Block[{k = 1, s = Sum[ a[i]*x^i, {i, 0, l - 1}]}, While[ IntegerQ[ Last[ CoefficientList[ Series[(s + k*x^l)^(1/n), {x, 0, l}], x]]] != True, k++ ]; k]; Table[ a[j], {j, 0, 32}]]; g[n_, m_] := f[n][[m]]; Flatten[ Table[ g[i, n - i], {n, 15}, {i, n - 1, 1, -1}]]

CROSSREFS

Rows: A111613, A083952, A083953, A083954, A083945, A083946, A083947, A083948, A083949, A083950, A084066, A084067.

Columns: A111613, A111627, A026741, A051176, A111607, A060791, A111608, A106608, A111609, A111610, A111611, A106612, A106614, A106618, A106620.

Diagonals: main=A000027, first upper=A111614, 2nd=A111627, 3rd=A111615, first lower=A111618, 2nd=A111623.

Other diagonals: T(2n-1, n)=A005408, A111626, A111627, A111628, A111629, A111630.

Cf. A111603, A111604.

Sequence in context: A182980 A108888 A124021 * A160182 A195825 A098824

Adjacent sequences:  A109623 A109624 A109625 * A109627 A109628 A109629

KEYWORD

nonn,tabl

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com) and Robert G. Wilson v (rgwv(AT)rgwv.com), Aug 01 2005

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Last modified February 17 16:13 EST 2012. Contains 206050 sequences.