A079721 Interemirp sequence: average of emirp pairs, analogous to interprimes.

15, 24, 34, 51, 72, 76, 88, 102, 110, 131, 153, 162, 173, 189, 255, 324, 342, 353, 374, 545, 705, 721, 736, 741, 747, 756, 765, 838, 922, 939, 947, 960, 969, 977, 987, 1000, 1015, 1026, 1032, 1047, 1065, 1080, 1094, 1100, 1106, 1130, 1152, 1167, 1187

Offset

1,1

Links

Table of n, a(n) for n=1..49.

M. J. Halm, Sequences

Formula

a(n) = (x(n)+x(n+1))/2 where x(n) is the n-th emirp number

Example

E.g. a(1) = 15 because the first two emirps are 13 and 17 and (13 + 17)/2 = 15

Crossrefs

Cf. A006567, A024675.

Sequence in context: A269316 A081829 A348730 * A362812 A089952 A373406

Adjacent sequences: A079718 A079719 A079720 * A079722 A079723 A079724

Keyword

nonn,base

Author

Michael Joseph Halm, Feb 17 2003

Status

approved