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A117134 Greatest k such that n^k divides (n^2)!. 0
3, 4, 7, 6, 17, 8, 21, 20, 24, 12, 70, 14, 32, 55, 63, 18, 80, 20, 99, 73, 48, 24, 191, 78, 56, 121, 130, 30, 224, 32, 204, 108, 72, 203, 323, 38, 80, 126, 398, 42, 293, 44, 193, 505, 96, 48, 575, 200, 312, 162, 225, 54, 485, 302, 522, 180, 120, 60, 898, 62, 128, 660, 682 (list; graph; refs; listen; history; internal format)
OFFSET

2,1

COMMENTS

If p is prime, a(p) = p+1, a(p^2) = floor((p^3 + p^2 + p + 1)/2)

REFERENCES

Thread "100!" in rec.puzzles newsgroup, April 2007

EXAMPLE

a(3)=4 because (3^2)! = 362880 = 3^4 * 4480 and 4480 is not divisible by 3

MAPLE

seq(ordp((n^2)!, n), n=2..50);

CROSSREFS

Cf. A011776.

Sequence in context: A077580 A069213 A130700 * A095001 A068905 A021746

Adjacent sequences:  A117131 A117132 A117133 * A117135 A117136 A117137

KEYWORD

nonn

AUTHOR

Robert B. Israel (israel(AT)math.ubc.ca), Apr 26 2007

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Last modified February 16 14:37 EST 2012. Contains 205930 sequences.