A124691 a(n) = lcm(prime(n)+1, prime(n+1)+1) / 2.

6, 6, 12, 12, 42, 63, 90, 60, 60, 240, 304, 399, 462, 264, 216, 270, 930, 1054, 612, 1332, 1480, 840, 630, 2205, 2499, 2652, 1404, 2970, 3135, 3648, 2112, 1518, 4830, 1050, 5700, 6004, 6478, 3444, 2436, 2610, 8190, 8736, 9312, 9603, 9900, 5300, 5936, 6384

Offset

1,1

Links

Table of n, a(n) for n=1..48.

Formula

a(n) = (1/2)*lcm(1+A000040(n), 1+A000040(1+n)).

Mathematica

f[n_] := LCM [Prime[n] + 1, Prime[n + 1] + 1]/2; Table[f@n, {n, 48}] (* Robert G. Wilson v, Jun 28 2007 *)

Crossrefs

Sequence in context: A315785 A127402 A161418 * A315786 A112437 A122223

Adjacent sequences: A124688 A124689 A124690 * A124692 A124693 A124694

Keyword

easy,nonn

Author

Philippe LALLOUET (philip.lallouet(AT)wanadoo.fr), Jun 26 2007

Extensions

More terms from Robert G. Wilson v, Jun 28 2007

Status

approved