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A077714
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a(1) = 1, a(n) = the smallest prime such that deleting the most significant digit gives a(n-1). If no such number exists then the smallest prime so that a(n-1) is obtained by deleting the two most significant digits. (In general by deleting as many minimum number of (most significant) digits required).
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3
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1, 11, 211, 4211, 34211, 234211, 4234211, 304234211, 9304234211, 209304234211, 7209304234211, 37209304234211, 3037209304234211, 23037209304234211, 323037209304234211, 70000323037209304234211, 300070000323037209304234211
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| a(n) is obtained by prefixing a(n-1) with a number of the form d*10^k where d is a single digit. 0< d < 10. Conjecture: There exists a number k however large for every term. i.e. Only one digit (MSD) need be deleted. In other words For every prime p there exists a prime q such that q = p + d*10^m where 0<d<10. Here m = k + number of digits in a(n-1).
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EXAMPLE
| a(7) = 50612113 deleting 5 gives 612113 = a(6).
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CROSSREFS
| Cf. A053582, A077713, A077715, A077716.
Sequence in context: A038399 A053547 A053582 * A089567 A110747 A112704
Adjacent sequences: A077711 A077712 A077713 * A077715 A077716 A077717
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KEYWORD
| base,nonn
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Nov 19 2002
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EXTENSIONS
| More terms from Ray Chandler (rayjchandler(AT)sbcglobal.net), Jul 23 2003
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