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A059836 Triangle T(s,t), s>=1, 1<=t<=s (see formula line). 1
1, 1, 1, 1, 2, 4, 1, 3, 9, 18, 1, 4, 16, 48, 144, 1, 5, 25, 100, 400, 1200, 1, 6, 36, 180, 900, 3600, 14400, 1, 7, 49, 294, 1764, 8820, 44100, 176400, 1, 8, 64, 448, 3136, 18816, 112896, 564480, 2822400, 1, 9, 81, 648, 5184, 36288, 254016, 1524096, 9144576 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,5

REFERENCES

S. G. Mikhlin, Constants in Some Inequalities of Analysis, Wiley, NY, 1986, see p. 59.

FORMULA

T(s, t) = (s-1)^2*(s-2)^2*...(s-(t-1)/2)^2 if t odd, else (s-1)^2*(s-2)^2*...(s-t/2+1)^2*(s-t/2).

EXAMPLE

1; 1,1; 1,2,4; 1,3,9,18; ...

MAPLE

T := proc(s, t) option remember: if s=1 or t=1 then RETURN(1) fi: if t>1 and t mod 2 = 1 then RETURN(product((s-i)^2, i=1..(t-1)/2)) else RETURN((s-t/2)*product((s-i)^2, i=1..t/2-1)) fi: end: for s from 1 to 15 do for t from 1 to s do printf(`%d, `, T(s, t)) od:od:

CROSSREFS

Cf. A059837.

Sequence in context: A076053 A158613 A100075 * A069270 A079901 A121426

Adjacent sequences:  A059833 A059834 A059835 * A059837 A059838 A059839

KEYWORD

nonn,easy,tabl

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Feb 25 2001

EXTENSIONS

More terms from James A. Sellers (sellersj(AT)math.psu.edu), Feb 26 2001 and from Larry Reeves (larryr(AT)acm.org), Feb 26 2001.

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Last modified February 17 21:13 EST 2012. Contains 206085 sequences.