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A068681 Primes formed by the concatenation n, n-2, n. 1
313, 757, 131113, 171517, 312931, 393739, 474547, 494749, 575557, 939193, 111109111, 127125127, 139137139, 147145147, 151149151, 169167169, 189187189, 213211213, 217215217, 227225227, 237235237, 239237239, 247245247, 253251253, 269267269, 331329331, 333331333, 353351353, 363361363, 377375377, 387385387, 389387389, 393391393 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..33.

EXAMPLE

111109111 is a term as it is the concatenation of 111, 109 and 111.

CROSSREFS

Cf. A068680.

Sequence in context: A104719 A087364 A090514 * A082436 A108845 A272442

Adjacent sequences:  A068678 A068679 A068680 * A068682 A068683 A068684

KEYWORD

base,easy,nonn

AUTHOR

Amarnath Murthy, Mar 02 2002

EXTENSIONS

More terms from Eli McGowan (ejmcgowa(AT)mail.lakeheadu.ca), Apr 11 2002

STATUS

approved

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Last modified January 22 07:39 EST 2020. Contains 331139 sequences. (Running on oeis4.)