A095720 a(1)=1 and, for n>1, a(n)=a(n-1)+Floor(3n/4) if n is even, else a(n)=smallest positive integer which has not yet appeared in the sequence.

1, 3, 2, 5, 4, 8, 6, 12, 7, 15, 9, 18, 10, 20, 11, 23, 13, 27, 14, 29, 16, 32, 17, 35, 19, 39, 21, 42, 22, 44, 24, 48, 25, 51, 26, 53, 28, 56, 30, 60, 31, 63, 33, 66, 34, 68, 36, 72, 37, 75, 38, 77, 40, 80, 41, 83, 43, 87, 45, 90, 46, 92, 47, 95, 49, 99, 50, 101, 52, 104, 54

Offset: 1

Author

John W. Layman, Jul 08 2004

Keywords

• nonn

Comments

Conjecture. For even n, the ratio a(n)/a(n-1) is asymptotic to 2 as n becomes large. (At n=3000, the ratio is 2.0004446.)

Crossrefs

Cf. A094077.