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A089913 Table T(n,k) = LCM(n,k)/GCD(n,k) = nk/GCD(n,k)^2 read by antidiagonals (n>=1, k>=1). 1
1, 2, 2, 3, 1, 3, 4, 6, 6, 4, 5, 2, 1, 2, 5, 6, 10, 12, 12, 10, 6, 7, 3, 15, 1, 15, 3, 7, 8, 14, 2, 20, 20, 2, 14, 8, 9, 4, 21, 6, 1, 6, 21, 4, 9, 10, 18, 24, 28, 30, 30, 28, 24, 18, 10, 11, 5, 3, 2, 35, 1, 35, 2, 3, 5, 11, 12, 22, 30, 36, 40, 42, 42, 40, 36, 30, 22, 12, 13, 6, 33, 10, 45 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

A multiplicative analogue of absolute difference A049581. Exponents in prime factorization of T(n,k) are absolute differences of those of n and k. Commutative non-associative operator with identity 1. T(nx,kx)=T(n,k), T(n^x,k^x)=T(n,k)^x, etc.

EXAMPLE

T(6,10) = LCM(6,10)/GCD(6,10) = 30/2 = 15.

CROSSREFS

Cf. A049581.

Sequence in context: A080045 A191384 A191305 * A059897 A071450 A072078

Adjacent sequences:  A089910 A089911 A089912 * A089914 A089915 A089916

KEYWORD

easy,nonn,tabl

AUTHOR

Marc LeBrun (mlb(AT)well.com), Nov 14 2003

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Last modified February 16 21:51 EST 2012. Contains 205978 sequences.