A034817 Concatenations C1 and C2 and C3 are all prime (see the comment lines).

63, 333, 621, 3339, 4557, 8127, 13977, 16827, 18177, 21921, 27393, 34989, 40023, 40047, 46917, 59727, 61203, 79467, 94767, 95079, 100821, 102771, 104859, 106527, 113883, 114123, 143433, 147123, 156201, 158409, 160149, 196737, 209277, 209961

Offset

0,1

Comments

C1 = 'prevprime(n) followed by n'

C2 = 'n followed by nextprime(n)'

C3 = 'prevprime(n) followed by n followed by nextprime(n)'

Links

Table of n, a(n) for n=0..33.

Example

n=95079 -> previous prime is 95071, next prime is 95083, thus '9501795079' and '9507995083' and '950719507995083' are all three primes.

Crossrefs

Cf. A034808-A034821.

Sequence in context: A138833 A204736 A160674 * A160895 A203556 A038993

Adjacent sequences: A034814 A034815 A034816 * A034818 A034819 A034820

Keyword

nonn,base

Author

Patrick De Geest, Oct 15 1998

Status

approved