A087341 - OEIS

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A087341

Smallest prime which is a concatenation of n successive composite numbers.

89, 138140141, 87889091, 8890919293, 141516182021, 122123124125126128129, 121122123124125126128129, 707274757677788081, 21222425262728303233, 206207208209210212213214215216217, 405406407408410411412413414415416417

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OFFSET

2,1

COMMENTS

a(3) contains three digit composite numbers as every concatenation of two digit numbers n,n+2 and n+3 is == 0 (mod 7).

LINKS

Table of n, a(n) for n=2..12.

G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 138140141.

G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 87889091.

EXAMPLE

a(2) = 89 is the concatenation of two successive composite numbers 8 and 9.

a(3) = 138140141 is the concatenation of 138,140 and 141.