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A033664 Every suffix is prime. 18
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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, Sep 24 2003

LINKS

T. D. Noe, Table of n, a(n) for n = 1..8779

Eric Weisstein's World of Mathematics, Truncatable Prime.

MATHEMATICA

h8pQ[n_]:=And@@PrimeQ/@Most[NestWhileList[FromDigits[Rest[ IntegerDigits[ #]]]&, n, #>0&]]; Select[Prime[Range[1000]], h8pQ] (* Harvey P. Dale, May 26 2011 *)

PROG

(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); )))) \\ Harry J. Smith, Sep 20 2008

(Haskell)

a033664 n = a033664_list !! (n-1)

a033664_list = filter (all ((== 1) . a010051. read) .

                           init . tail . tails . show) a000040_list

-- Reinhard Zumkeller, Jul 10 2013

CROSSREFS

Cf. A024785, A032437, A020994, A024770, A052023, A052024, A052025, A050986, A050987, A069866, A038680, A010051, A000040.

Sequence in context: A234695 A067905 A042993 * A024785 A069866 A125772

Adjacent sequences:  A033661 A033662 A033663 * A033665 A033666 A033667

KEYWORD

nonn,base,easy,nice

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Erich Friedman.

STATUS

approved

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Last modified December 4 17:35 EST 2016. Contains 278755 sequences.