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A068651
Primes in which a string of 2's is sandwiched between two 9's.
7
929, 9222229, 9222222222229
OFFSET
1,1
COMMENTS
The next term consists of 109 2's sandwiched between two 9's. - Sascha Kurz, Mar 27 2002
FORMULA
a(n) = (83*10^A056265(n) + 61)/9 = (83*10^A082718(n-2) + 61)/9.
CROSSREFS
KEYWORD
base,nonn,bref
AUTHOR
Amarnath Murthy, Feb 28 2002
EXTENSIONS
Edited by Ray Chandler, Oct 20 2010
Edited by Ray Chandler, Nov 05 2014
STATUS
approved