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A075599
a(1) = 7 and then the smallest prime that is obtained by placing digits on both sides of the previous term. Or smallest prime that encompasses a(n-1).
7
7, 173, 11731, 2117317, 421173173, 34211731733, 1342117317337, 813421173173377, 28134211731733771, 4281342117317337713, 142813421173173377131, 21428134211731733771317, 2214281342117317337713171, 2221428134211731733771317113, 922214281342117317337713171139
OFFSET
1,1
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Sep 28 2002
EXTENSIONS
More terms from Sascha Kurz, Jan 20 2003
Further terms from Ray G. Opao, Nov 26 2004
STATUS
approved