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A128264 Triangle read by rows, 1 <= m <= n: t(n,m) = lcm(s(n,m), S(n,m)), where s(n,m) is an unsigned Stirling number of the first kind and S(n,m) is a Stirling number of the second kind. 2
1, 1, 1, 2, 3, 1, 6, 77, 6, 1, 24, 150, 175, 10, 1, 120, 8494, 450, 1105, 15, 1, 720, 1764, 69832, 7350, 700, 21, 1, 5040, 1659636, 906108, 1644867, 29400, 6118, 28, 1, 40320, 9314640, 357325100, 12447540, 7430619, 31752, 6006, 36, 1, 362880, 524580336 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..47.

FORMULA

T(n,m) = lcm(A008277(n,m), |A008275(n,m)|). - R. J. Mathar, Sep 24 2007

EXAMPLE

Triangle starts

    1;

    1,    1;

    2,    3,     1;

    6,   77,     6,    1;

   24,  150,   175,   10,   1;

  120, 8494,   450, 1105,  15,  1;

  720, 1764, 69832, 7350, 700, 21, 1;

MAPLE

A128264 := proc(n, m) lcm(combinat[stirling1](n, m), combinat[stirling2](n, m)) ; end: for n from 1 to 10 do for m from 1 to n do printf("%d, ", A128264(n, m)) ; od: od: # R. J. Mathar, Sep 24 2007

PROG

(PARI) tabl(nn) = {for (n=1, nn, for (k=1, n, print1(lcm(stirling(n, k, 1), stirling(n, k, 2)), ", "); ); print(); ); } \\ Michel Marcus, Aug 18 2015

CROSSREFS

Cf. A128265.

Cf. A000142 (T(n,1)), A000217 (T(n, n-1)).

Sequence in context: A130850 A130405 A058372 * A232435 A114858 A193491

Adjacent sequences:  A128261 A128262 A128263 * A128265 A128266 A128267

KEYWORD

nonn,tabl

AUTHOR

Leroy Quet, Feb 22 2007

EXTENSIONS

More terms from R. J. Mathar, Sep 24 2007

STATUS

approved

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Last modified August 12 16:40 EDT 2020. Contains 336439 sequences. (Running on oeis4.)