A069614 a(1) = 2; a(2n) = smallest prime starting (the most significant digits) with a(2n-1) (i.e., as a right concatenation of a(2n-1) and a number with no insignificant zeros); a(2n+1) = smallest prime ending in (the least significant digits) a(2n-1). Alternate left and right concatenation yielding primes.

2, 23, 223, 2237, 32237, 3223729, 63223729, 632237297, 2632237297, 263223729721, 12263223729721, 1226322372972173, 171226322372972173, 17122632237297217381, 2117122632237297217381, 21171226322372972173813

Offset

1,1

Links

Table of n, a(n) for n=1..16.

Example

a(4) = 2111 staring with a(3) = 211 and a(5) = 22111 ending in a(4) = 2111.

Crossrefs

Cf. A053582, A069605, A069606, A069607, A069608, A069609, A069610, A069611, A069613.

Sequence in context: A069837 A376434 A069629 * A036937 A083808 A252016

Adjacent sequences: A069611 A069612 A069613 * A069615 A069616 A069617

Keyword

nonn,base

Author

Amarnath Murthy, Mar 27 2002

Extensions

More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Mar 30 2003

Status

approved