A379055 a(n) = composite(2*n+3) - composite(2*n+1).

4, 2, 4, 2, 4, 2, 3, 2, 3, 3, 2, 3, 2, 4, 2, 3, 2, 3, 2, 2, 4, 2, 2, 3, 3, 3, 2, 3, 2, 3, 2, 3, 2, 2, 2, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 3, 3, 2, 2, 4, 2, 2, 2, 2, 4, 2, 2, 3, 2, 3, 2, 3, 2, 3, 2, 2, 4, 2, 2, 2, 2, 4, 2, 4, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 3, 2, 4, 2

Offset

0,1

Links

Paolo Xausa, Table of n, a(n) for n = 0..10000

Mathematica

Differences[Select[Range[300], CompositeQ][[;; ;; 2]]] (* Paolo Xausa, Dec 18 2024 *)

Crossrefs

First differences of A099861.

Cf. A002808, A099861, A379054.

Sequence in context: A064127 A178253 A209272 * A105397 A373422 A328999

Adjacent sequences: A379052 A379053 A379054 * A379056 A379057 A379058

Keyword

nonn,changed

Author

N. J. A. Sloane, Dec 18 2024

Status

approved