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A127889
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Smallest n-digit right-truncatable prime.
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4
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OFFSET
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1,1
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COMMENTS
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Agrees with A088603 for 8 terms, but this sequence ends there while A088603 continues.
Right-truncatable means that the integer part of successive divisions by 10 always yields primes (or zero). - M. F. Hasler, Nov 07 2018
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LINKS
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Table of n, a(n) for n=1..8.
I. O. Angell and H. J. Godwin, On Truncatable Primes, Math. Comput. 31, 265-267, 1977.
Index entries for sequences related to truncatable primes
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MAPLE
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P:=proc(q) local i, j, n, ok; for i from 0 to 8 do for n from 1 to q do ok:=1;
for j from 1 to i do if not isprime(trunc(ithprime(n)/10^j)) then ok:=0;
break; fi; od; if ok=1 then print(ithprime(n)); break; fi;
od; od; end: P(23399339); # Paolo P. Lava, Oct 15 2013
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PROG
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(PARI) A127889=vector(8, n, p=concat(apply(t->primes([t, t+1]*10), if(n>1, p))); p[1]) \\ M. F. Hasler, Nov 07 2018
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CROSSREFS
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Cf. A024770, A050986, A088603, A127890.
Sequence in context: A100893 A198972 A065122 * A088603 A048549 A158191
Adjacent sequences: A127886 A127887 A127888 * A127890 A127891 A127892
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KEYWORD
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base,nonn,fini,full
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AUTHOR
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Ray Chandler, Feb 04 2007
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STATUS
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approved
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