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A009223 GCD(sigma(n), phi(n)). 10
1, 1, 2, 1, 2, 2, 2, 1, 1, 2, 2, 4, 2, 6, 8, 1, 2, 3, 2, 2, 4, 2, 2, 4, 1, 6, 2, 4, 2, 8, 2, 1, 4, 2, 24, 1, 2, 6, 8, 2, 2, 12, 2, 4, 6, 2, 2, 4, 3, 1, 8, 2, 2, 6, 8, 24, 4, 2, 2, 8, 2, 6, 4, 1, 12, 4, 2, 2, 4, 24, 2, 3, 2, 6, 4, 4, 12, 24, 2, 2, 1, 2, 2, 8, 4, 6, 8, 20, 2, 6, 8, 4, 4, 2, 24, 4, 2, 3, 12, 1, 2, 8 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..102.

MATHEMATICA

Table[GCD[DivisorSigma[1, n], EulerPhi[n]], {n, 110}] (* From Harvey P. Dale, Aug 10 2011 *)

CROSSREFS

Sequence in context: A082064 A082055 A073812 * A110244 A055188 A164885

Adjacent sequences:  A009220 A009221 A009222 * A009224 A009225 A009226

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified May 19 12:53 EDT 2013. Contains 225429 sequences.