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A066575 LCM of numbers m such that 1 <= m <= n, m has a common factor with n, but m does not divide n. 0
1, 1, 1, 1, 1, 4, 1, 6, 6, 24, 1, 360, 1, 120, 180, 420, 1, 1680, 1, 5040, 1260, 5040, 1, 55440, 60, 55440, 2520, 720720, 1, 10810800, 1, 360360, 83160, 1441440, 2100, 73513440, 1, 24504480, 1081080, 2327925600, 1, 1396755360, 1, 465585120 (list; graph; refs; listen; history; internal format)
OFFSET

1,6

EXAMPLE

a(12) = 360 = LCM(8,9,10) as 8, 9 and 10 are the only numbers <= 12 which are not relatively prime to 12 nor do they divide 12.

MAPLE

for i from 1 to 100 do a := 1:for j from 1 to i do b := igcd(i, j); if(b>1 and b<j) then a := ilcm(a, j):end if:end do:c[i] := a; end do:q := seq(c[k], k=1..100);

CROSSREFS

Sequence in context: A021100 A021028 A193529 * A070251 A134234 A205137

Adjacent sequences:  A066572 A066573 A066574 * A066576 A066577 A066578

KEYWORD

nonn

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Dec 19 2001

EXTENSIONS

More terms from Sascha Kurz (sascha.kurz(AT)uni-bayreuth.de), Mar 23 2002

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Last modified February 17 14:50 EST 2012. Contains 206050 sequences.