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A160966 Starting from a(1)=2, a(n) = A028260(1+a(n-1)) if n is even, a(n) = A026424(a(n-1)) if n is odd. 0
2, 6, 11, 25, 45, 94, 176, 361, 700, 1405, 2752, 5533, 10964, 22011, 43839, 87868, 175557, 351746, 703243, 1407705, 2814709, 5631461, 11261009, 22524901, 45044446, 90091251, 180165450, 360333977, 720640449, 1441293048, 2882532607 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

If a(1) were set to 3, the equivalent sequence would start 3, 9, 17, 38, 71, 146, 279,...

Alternatively starting from a(1)=4 we get 4, 10, 18, 39, 72, 150,..

LINKS

Table of n, a(n) for n=1..31.

EXAMPLE

a(2)= 6, the second integer containing an even number of prime factors.

a(3)= 11, the sixth integer containing an odd number of primes.

CROSSREFS

Cf. A141436

Sequence in context: A067605 A072986 A079047 * A052326 A079118 A211054

Adjacent sequences:  A160963 A160964 A160965 * A160967 A160968 A160969

KEYWORD

nonn

AUTHOR

Daniel Tisdale, May 31 2009

EXTENSIONS

Definition clarified, sequence extended beyond 25 by R. J. Mathar, May 31 2010

a(15)-a(31) from Donovan Johnson, Jul 02 2010

STATUS

approved

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Last modified April 25 16:08 EDT 2019. Contains 322461 sequences. (Running on oeis4.)