A089713 - OEIS

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A089713

a(n) is the largest prime that is the concatenation of n and m for some m < n, or 0 if no such prime exists.

0, 0, 31, 43, 53, 61, 73, 83, 97, 109, 113, 127, 139, 149, 1511, 1613, 179, 1811, 1913, 2017, 2113, 2221, 2311, 2423, 2521, 2621, 2719, 2819, 2927, 3023, 3121, 3229, 3331, 3433, 3533, 3631, 3733, 3833, 3931, 4027, 4139, 4241, 4339, 4441, 4523, 4643, 4733

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OFFSET

1,3

COMMENTS

Does this prime exist for all n > 2?

LINKS

Table of n, a(n) for n=1..47.

CROSSREFS

Cf. A070219, A089715.

Sequence in context: A364149 A101520 A225862 * A281246 A067467 A317851

Adjacent sequences: A089710 A089711 A089712 * A089714 A089715 A089716

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Nov 17 2003

EXTENSIONS

Edited by David Wasserman, Feb 05 2004

STATUS

approved