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A096461 a(1)=1, a(2)=2; for n >= 2, a(n+1) = a(n) + sum of prime factors of a(n). 5
1, 2, 4, 8, 14, 23, 46, 71, 142, 215, 263, 526, 791, 911, 1822, 2735, 3287, 3479, 3564, 3591, 3626, 3679, 3975, 4041, 4496, 4785, 4833, 5021, 10042, 15065, 15224, 15414, 15793, 16739, 17639, 18239, 18336, 18540, 18658, 19170, 19257, 19405, 23291 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

FORMULA

a(n+1) = A075254(a(n)) for n > 1. [Reinhard Zumkeller, Feb 27 2012]

EXAMPLE

Given a(4)=8 whose prime factorization is 2*2*2, add to a(4) its prime factors (2+2+2)=6 to give a(5)=8+6=14.

MATHEMATICA

a[1] := 1; a[n_] := a[n] = a[n - 1] + Plus@@Times@@@FactorInteger@a[n - 1]; Table[a[n], {n, 40}] (* Alonso del Arte, Jul 12 2011 *)

NestList[#+Total[Times@@@FactorInteger[#]]&, 1, 45] (* Harvey P. Dale, Nov 16 2011 *)

PROG

(Haskell)

a096461 n = a096461_list !! (n-1)

a096461_list = 1 : iterate a075254 2  -- Reinhard Zumkeller, Feb 27 2012

CROSSREFS

Sequence in context: A202840 A018153 A101687 * A049701 A005598 A100250

Adjacent sequences:  A096458 A096459 A096460 * A096462 A096463 A096464

KEYWORD

nonn,nice

AUTHOR

Gil Broussard, Aug 12 2004

EXTENSIONS

Definition corrected by N. J. A. Sloane, Jul 16 2007

STATUS

approved

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Last modified March 25 01:30 EDT 2017. Contains 284036 sequences.