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A070220 Primes of the form n (written in base 10) followed by n 1's. 1
11, 211, 511111, 71111111, 101111111111, 161111111111111111, 2011111111111111111111, 6511111111111111111111111111111111111111111111111111111111111111111 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

MATHEMATICA

Do[p = FromDigits[ Join[ IntegerDigits[n], IntegerDigits[(10^n - 1)/9]]]; If[ PrimeQ[p], Print[p]], {n, 1, 100}]

CROSSREFS

Cf. A068817 (for values of n).

Sequence in context: A112704 A114758 A088061 * A134069 A137464 A187650

Adjacent sequences:  A070217 A070218 A070219 * A070221 A070222 A070223

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), May 02 2002

EXTENSIONS

More terms from Vladeta Jovovic (vladeta(AT)eunet.rs) and Robert G. Wilson v (rgwv(AT)rgwv.com), May 03 2002

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Last modified February 13 18:14 EST 2012. Contains 205534 sequences.