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A066813 a(n) = lcm(phi(n), phi(n+1)). 5
1, 2, 2, 4, 4, 6, 12, 12, 12, 20, 20, 12, 12, 24, 8, 16, 48, 18, 72, 24, 60, 110, 88, 40, 60, 36, 36, 84, 56, 120, 240, 80, 80, 48, 24, 36, 36, 72, 48, 80, 120, 84, 420, 120, 264, 506, 368, 336, 420, 160, 96, 312, 468, 360, 120, 72, 252, 812, 464, 240, 60, 180, 288, 96 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..1000

MATHEMATICA

LCM@@EulerPhi[#]&/@Partition[Range[100], 2, 1] (* Harvey P. Dale, May 07 2011 *)

PROG

(PARI) { for (n=1, 1000, write("b066813.txt", n, " ", lcm(eulerphi(n), eulerphi(n+1))) ) } \\ Harry J. Smith, Mar 29 2010

CROSSREFS

Sequence in context: A128745 A188524 A126064 * A033732 A033752 A059886

Adjacent sequences:  A066810 A066811 A066812 * A066814 A066815 A066816

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Jan 20 2002

STATUS

approved

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Last modified December 2 13:03 EST 2016. Contains 278678 sequences.