A075339 a(1) = 1, a(2n) = smallest composite number obtained by adding a prime to a(2n-1). a(2n+1) = the smallest prime obtained by adding a composite number to a(2n).

1, 4, 13, 15, 19, 21, 29, 32, 41, 44, 53, 55, 59, 62, 71, 74, 83, 85, 89, 91, 97, 99, 103, 105, 109, 111, 127, 129, 137, 140, 149, 152, 167, 169, 173, 175, 179, 182, 191, 194, 227, 230, 239, 242, 251, 253, 257, 259, 263, 265, 269, 272, 281, 284, 293, 295, 307

Offset

1,2

Comments

a(k) = b(k-1) for k > 6 where b(r) is the r-th term of A075338.

Links

Table of n, a(n) for n=1..57.

Crossrefs

Cf. A075338.

Sequence in context: A066825 A014563 A066774 * A089733 A126908 A106681

Adjacent sequences: A075336 A075337 A075338 * A075340 A075341 A075342

Keyword

nonn

Author

Amarnath Murthy, Sep 18 2002

Extensions

More terms from David Wasserman, Jan 16 2005

Status

approved