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A078558 GCD of sigma[A002110(n)] and phi[A002110(n)]. 2
1, 2, 8, 48, 96, 1152, 9216, 1658880, 3317760, 92897280, 2786918400, 100329062400, 802632499200, 370816214630400, 741632429260800, 2966529717043200, 29665297170432000, 355983566045184000 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

FORMULA

a(n)=GCD[A000203[A002110(n)], A000005[A002110(n)]]= GCD[A005867(n), A054640(n)]

EXAMPLE

m=2,3,30,210 primorials are balanced numbers so theses GCD() equals phi(): a[m]=1,2,8,48 (see A005867).

CROSSREFS

Cf. A000203, A002110, A000005, A005867, A054640, A020492.

Sequence in context: A199136 A181413 A003275 * A003032 A193944 A058928

Adjacent sequences:  A078555 A078556 A078557 * A078559 A078560 A078561

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Dec 06 2002

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Last modified February 17 14:12 EST 2012. Contains 206031 sequences.