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A116370 Number of distinct prime factors of P(L(n)) where L(n) is the Lucas number and P(n) is the unrestricted partition number. 1
1, 1, 2, 2, 3, 3, 4, 2, 2, 3, 4, 5, 4, 4, 5, 5, 8, 10, 6, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,3

LINKS

Table of n, a(n) for n=2..21.

EXAMPLE

P(L(14)) = 37285884524590579748861394570 = 2 * 3^2 * 5 * 414287605828784219431793273, so the 13th number in the sequence is 4.

MAPLE

A000041 := proc(n) combinat[numbpart](n) ; end: A000204 := proc(n) option remember ; if n = 1 then 1; elif n = 2 then 3 ; else A000204(n-1)+A000204(n-2) ; fi ; end: A116370 := proc(n) local fcts ; fcts := A000041(A000204(n)) ; nops(numtheory[factorset](fcts)) ; end: for n from 2 to 20 do print(A116370(n)) ; od: # R. J. Mathar, Jan 30 2008

MATHEMATICA

PrimeNu[PartitionsP[LucasL[Range[2, 21]]]] (* Harvey P. Dale, Apr 07 2018 *)

CROSSREFS

Sequence in context: A322997 A085561 A260651 * A261018 A106486 A195743

Adjacent sequences:  A116367 A116368 A116369 * A116371 A116372 A116373

KEYWORD

more,nonn

AUTHOR

Parthasarathy Nambi, Mar 15 2006

EXTENSIONS

2 more terms from R. J. Mathar, Jan 30 2008

a(17)-a(21) from Donovan Johnson, Aug 31 2008

STATUS

approved

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Last modified July 15 22:38 EDT 2020. Contains 335774 sequences. (Running on oeis4.)