A103934 Choose a(n) to be the smallest odd number not yet used such that: a(1) = 1, a(2n) = prime, a(2n+1) = composite and partial sums are alternately composite or prime.

1, 3, 9, 5, 25, 7, 21, 11, 15, 13, 27, 17, 39, 19, 45, 23, 33, 29, 55, 31, 35, 37, 57, 41, 49, 43, 119, 47, 51, 53, 91, 59, 77, 61, 125, 67, 143, 71, 69, 73, 65, 79, 63, 83, 75, 89, 121, 97, 81, 101, 99, 103, 87, 107, 117, 109, 135, 113, 93, 127, 111, 131, 129, 137, 115, 139

Offset

1,2

Links

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

Crossrefs

Cf. A075593, A075594, A103824, A103825, A103935.

Sequence in context: A143218 A262024 A252117 * A365203 A186814 A077384

Adjacent sequences: A103931 A103932 A103933 * A103935 A103936 A103937

Keyword

nonn

Author

Ray Chandler Feb 21 2005, based on a suggestion from Zak Seidov.

Status

approved