A083470 Smallest prime which is the concatenation of n distinct primes in increasing order.

2, 23, 257, 2357, 235723, 23571143, 2357111371, 235711131767, 23571113172367, 2357111317192343, 235711131719233171, 23571113171923296797, 2357111317192329314189, 235711131719232931375979, 23571113171923293137414371, 2357111317192329313741436167

Offset

1,1

Comments

Perhaps the n-th term begins with the concatenation of the first n-1 primes, except for n = 3.

The 9th, 11th, 12th, 13th, .... terms are other counterexamples to the above "conjecture". On the other hand, it seems almost sure that the n-th term starts with the concatenation of the first n-2 primes. - M. F. Hasler, Mar 20 2011

There are counterexamples to Hasler as well. For example, a(23) = 235711131719232931374147535961677173798997 (which misses 43). Such extreme cases are more likely to happen near boundaries when the number of digits in the primes increases. - Sean A. Irvine, Jan 28 2026

Links

Sean A. Irvine, Table of n, a(n) for n = 1..150

Crossrefs

Cf. A069837, A083427.

Sequence in context: A300326 A068983 A083427 * A064110 A176936 A126040

Adjacent sequences: A083467 A083468 A083469 * A083471 A083472 A083473

Keyword

base,nonn

Author

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 02 2003

Extensions

More terms from David Wasserman, Nov 02 2004

Status

approved