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A033664
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Every suffix is prime.
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16
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2, 3, 5, 7, 13, 17, 23, 37, 43, 47, 53, 67, 73, 83, 97, 103, 107, 113, 137, 167, 173, 197, 223, 283, 307, 313, 317, 337, 347, 353, 367, 373, 383, 397, 443, 467, 503, 523, 547, 607, 613, 617, 643, 647, 653, 673, 683, 743, 773, 797, 823, 853, 883, 907, 937, 947
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internal format)
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OFFSET
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1,1
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COMMENTS
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Primes in which repeatedly deleting the most significant digit gives a prime at every step until a single digit prime remains.
Every digit string containing the least significant digit is prime. - Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Sep 24 2003
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LINKS
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T. D. Noe, Table of n, a(n) for n=1..8779
Eric Weisstein's World of Mathematics, Truncatable Prime.
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MATHEMATICA
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h8pQ[n_]:=And@@PrimeQ/@Most[NestWhileList[FromDigits[Rest[ IntegerDigits[#]]]&, n, #>0&]]; Select[Prime[Range[1000]], h8pQ] (* From Harvey P. Dale, May 26 2011 *)
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PROG
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(PARI) {fileO="b033664.txt"; lim=8779; v=vector(lim); v[1]=2; v[2]=3; v[3]=5; v[4]=7; j=4; write(fileO, "1 2"); write(fileO, "2 3"); write(fileO, "3 5"); write(fileO, "4 7"); p10=1; until(0, p10*=10; j0=j; for(k=1, 9, k10=k*p10; for(i=1, j0, if(j==lim, break(3)); z=k10+v[i]; if(isprime(z), j++; v[j]=z; write(fileO, j, " ", z); )))); } [From Harry J. Smith, Sep 20 2008]
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CROSSREFS
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Cf. A024785, A032437, A020994, A024770, A052023, A052024, A052025, A050986, A050987.
Cf. A024770, A069866.
Sequence in context: A155777 A067905 A042993 * A024785 A069866 A125772
Adjacent sequences: A033661 A033662 A033663 * A033665 A033666 A033667
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KEYWORD
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nonn,base,easy,nice
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AUTHOR
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N. J. A. Sloane.
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EXTENSIONS
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More terms from Erich Friedman.
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STATUS
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approved
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