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A103824 Choose a(n) to be the smallest number not yet used such that: a(1) = 1, a(2n) = prime, a(2n+1) = composite and partial sums are alternately composite or prime. 5
1, 3, 9, 2, 4, 5, 35, 7, 65, 11, 15, 13, 21, 17, 25, 19, 55, 23, 49, 29, 91, 31, 27, 37, 115, 41, 77, 43, 121, 47, 85, 53, 125, 59, 39, 61, 33, 67, 133, 71, 143, 73, 119, 79, 95, 83, 81, 89, 145, 97, 51, 101, 99, 103, 45, 107, 57, 109, 87, 113, 69, 127, 75, 131, 111, 137 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..66.

CROSSREFS

Cf. A075593, A075594, A103825.

Sequence in context: A275371 A225357 A201664 * A155080 A010780 A309275

Adjacent sequences:  A103821 A103822 A103823 * A103825 A103826 A103827

KEYWORD

nonn

AUTHOR

Ray Chandler Feb 16 2005

EXTENSIONS

Definition corrected by Zak Seidov, Feb 20 2005

STATUS

approved

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Last modified April 14 20:23 EDT 2021. Contains 342962 sequences. (Running on oeis4.)