A160680 - OEIS

A160680

a(n) = sigma_0(F(n-1)) + sigma_0(F(n-2)) where F=A000045 and sigma_0=A000005.

2, 3, 4, 4, 6, 6, 6, 8, 8, 6, 17, 17, 6, 12, 16, 10, 18, 20, 20, 24, 12, 6, 74, 78, 10, 20, 32, 18, 66, 68, 20, 24, 12, 12, 168, 168, 16, 16, 72, 68, 68, 66, 34, 64, 40, 10, 338, 344, 56, 56, 24, 20, 132, 144, 112, 128, 40, 12, 964, 964, 12, 40, 96, 72, 72, 72, 40, 64, 160

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OFFSET

3,1

LINKS

Table of n, a(n) for n=3..71.

FORMULA

a(n) = A063375(n-1) + A063375(n-2). - R. J. Mathar, May 25 2009, Jun 01 2009

MAPLE

A063375 := proc(n) A000005(A000045(n)) ; end: A000045 := proc(n) combinat[fibonacci](n) ; end: A000005 := proc(n) numtheory[tau](n) ; end: for n from 3 to 120 do printf("%d, ", A063375(n-1)+A063375(n-2)) ; od: # R. J. Mathar, May 25 2009

MATHEMATICA

Join[{1, 1}, Total[DivisorSigma[0, #]]&/@Partition[Fibonacci[Range[70]], 2, 1]] (* Harvey P. Dale, Mar 07 2012 *)

CROSSREFS

Cf. A000005, A000045, A063375.

Sequence in context: A265533 A145340 A307989 * A243069 A342496 A061984

Adjacent sequences: A160677 A160678 A160679 * A160681 A160682 A160683

KEYWORD

easy,nonn

AUTHOR

Ctibor O. Zizka, May 23 2009

EXTENSIONS

More terms from R. J. Mathar, May 25 2009

Offset changed to 3. - R. J. Mathar, Jun 19 2021

STATUS

approved