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A121875 Triangular array read by rows: see Comments for definition. 1
1, 2, 3, 3, 7, 13, 5, 17, 43, 89, 8, 41, 142, 377, 836, 13, 99, 469, 1597, 4341, 10063, 21, 239, 1549, 6765, 22541, 62011, 148149, 34, 577, 5116, 28657, 117046, 382129, 1057792, 2581921, 55, 1393, 16897, 121393, 607771, 2354785, 7552693, 20973217 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Form the square array in which row m satisfies r(0) = r(1) = 1; r(n) = m*r(n-1) + r(n-2):

1 1 2 3 5 8 13 21 ...

1 1 3 7 17 41 99 ...

1 1 4 13 43 142 ...

1 1 5 21 89 377 ...

...

Now form a triangle by taking the first k terms of column k:

1

2, 3

3, 7, 13

5, 17, 43, 89

8, 41, 142, 377, 836

...

LINKS

Table of n, a(n) for n=1..44.

MATHEMATICA

f[n_Integer] = Module[{a}, a[n] /. RSolve[{a[n] == m*a[n - 1] + a[n - 2], a[0] == 1, a[1] == 1}, a[n], n][[1]] // FullSimplify] a = Table[Table[Rationalize[N[f[n], 100], 0], {m, 1, n}], {n, 1, 10}] Flatten[a]

CROSSREFS

Cf. A135597.

Sequence in context: A169653 A129012 A136122 * A036251 A176022 A316275

Adjacent sequences:  A121872 A121873 A121874 * A121876 A121877 A121878

KEYWORD

nonn,tabl

AUTHOR

Roger L. Bagula and Gary W. Adamson, Sep 09 2006

EXTENSIONS

Edited by N. J. A. Sloane, Mar 02 2008

STATUS

approved

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Last modified October 15 10:15 EDT 2019. Contains 328026 sequences. (Running on oeis4.)