id:A082065 - OEIS Search Results

Search: id:A082065

Displaying 1-1 of 1 results found.

page 1

A082065

Greatest common prime-divisor of Phi[n]=A000010(n) and Sigma[2,n]=A001157(n); a(n)=1 if no common prime-divisor was found.

+0
4

1, 1, 2, 1, 2, 2, 2, 1, 1, 2, 2, 2, 2, 3, 2, 1, 2, 3, 2, 2, 2, 2, 2, 2, 1, 3, 2, 2, 2, 2, 2, 1, 2, 2, 3, 1, 2, 3, 2, 2, 2, 3, 2, 2, 3, 2, 2, 2, 3, 1, 2, 2, 2, 3, 2, 3, 2, 2, 2, 2, 2, 3, 2, 1, 3, 2, 2, 2, 2, 3, 2, 3, 2, 3, 2, 2, 3, 3, 2, 2, 1, 2, 2, 2, 2, 3, 2, 5, 2, 3, 2, 2, 2, 2, 3, 2, 2, 3, 3, 1, 2, 2, 2, 3, 3 (list; graph; listen)

	OFFSET	`1,3`
	MATHEMATICA	`ffi[x_] := Flatten[FactorInteger[x]] lf[x_] := Length[FactorInteger[x]] ba[x_] := Table[Part[ffi[x], 2*w-1], {w, 1, lf[x]}] f1[x_] := EulerPhi[n]; f2[x_] := DivisorSigma[2, x] Table[Max[Intersection[ba[f1[w]], ba[f2[w]]]], {w, 1, 128}]`
	CROSSREFS	`Cf. A006530, A001157, A000010, A082061-A082066.` `Sequence in context: A082902 A123926 A082064 this_sequence A082055 A073812 A009223` `Adjacent sequences: A082062 A082063 A082064 this_sequence A082066 A082067 A082068`
	KEYWORD	`nonn`
	AUTHOR	`Labos E. (labos(AT)ana.sote.hu), Apr 07 2003`

page 1

Search completed in 0.002 seconds

Last modified December 20 16:54 EST 2009. Contains 171081 sequences.

AT&T Labs Research