id:A082054 - OEIS Search Results

Search: id:A082054

Displaying 1-1 of 1 results found.

page 1

A082054

Sum of common prime-divisors[without multiplicity] of sigma[n] and phi[n].

+0
4

0, 0, 2, 0, 2, 2, 2, 0, 0, 2, 2, 2, 2, 5, 2, 0, 2, 3, 2, 2, 2, 2, 2, 2, 0, 5, 2, 2, 2, 2, 2, 0, 2, 2, 5, 0, 2, 5, 2, 2, 2, 5, 2, 2, 5, 2, 2, 2, 3, 0, 2, 2, 2, 5, 2, 5, 2, 2, 2, 2, 2, 5, 2, 0, 5, 2, 2, 2, 2, 5, 2, 3, 2, 5, 2, 2, 5, 5, 2, 2, 0, 2, 2, 2, 2, 5, 2, 7, 2, 5, 2, 2, 2, 2, 5, 2, 2, 3, 5, 0, 2, 2, 2, 5, 5 (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]}] Table[Apply[Plus, Intersection[ba[EulerPhi[w]], ba[DivisorSigma[1, w]]]], {w, 1, 256}]`
	CROSSREFS	`Cf. A000203, A000010.` `Sequence in context: A112803 A124242 A112274 this_sequence A044943 A102395 A127504` `Adjacent sequences: A082051 A082052 A082053 this_sequence A082055 A082056 A082057`
	KEYWORD	`nonn`
	AUTHOR	`Labos E. (labos(AT)ana.sote.hu), Apr 03 2003`

page 1

Search completed in 0.002 seconds

Last modified November 27 14:50 EST 2009. Contains 167570 sequences.

AT&T Labs Research