A103935 Choose a(n) to be the smallest odd number not yet used such that: a(1) = 1, a(2n) = composite, a(2n+1) = prime and partial sums are alternately composite or prime.

1, 9, 3, 15, 13, 21, 5, 25, 11, 27, 7, 33, 23, 35, 29, 39, 17, 45, 31, 49, 19, 51, 61, 55, 37, 57, 43, 63, 53, 65, 41, 69, 71, 75, 79, 77, 73, 81, 59, 85, 47, 87, 103, 91, 83, 93, 113, 95, 109, 99, 127, 105, 149, 111, 139, 115, 89, 117, 107, 119, 97, 121, 131, 123, 67, 125

Offset

1,2

Links

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

Crossrefs

Cf. A075593, A075594, A103824, A103825, A103934.

Sequence in context: A329653 A170874 A309791 * A040077 A195312 A248311

Adjacent sequences: A103932 A103933 A103934 * A103936 A103937 A103938

Keyword

nonn

Author

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

Status

approved