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Every suffix of palindromic prime a(n), containing no '0' digit, is prime (left-truncatable palindromic primes).
12

%I #27 Aug 11 2024 14:41:32

%S 2,3,5,7,313,353,373,383,797,76367,79397,7693967,799636997

%N Every suffix of palindromic prime a(n), containing no '0' digit, is prime (left-truncatable palindromic primes).

%H I. O. Angell and H. J. Godwin, <a href="http://dx.doi.org/10.1090/S0025-5718-1977-0427213-2">On Truncatable Primes</a>, Math. Comput. 31, 265-267, 1977.

%H C. K. Caldwell, <a href="https://t5k.org/glossary/page.php?sort=LeftTruncatablePrime">Left</a> and <a href="https://t5k.org/glossary/page.php?sort=RightTruncatablePrime">Right</a> truncatable primes.

%H P. De Geest, <a href="https://www.worldofnumbers.com/truncat.htm">The list of 4260 left-truncatable primes</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimeString.html">Prime strings</a>

%H <a href="/index/Tri#tprime">Index entries for sequences related to truncatable primes</a>

%t d[n_]:=IntegerDigits[n]; ltrQ[n_]:=And@@PrimeQ[NestList[FromDigits[Drop[d[#],1]]&,n,Length[d[n]]-1]]; palQ[n_]:=Reverse[x=d[n]]==x; Select[Prime[Range[540000]],palQ[#]&&ltrQ[#]&] (* _Jayanta Basu_, Jun 02 2013 *)

%Y Cf. A033664, A024785, A032437, A020994, A024770, A052024, A052025, A050986, A050987.

%K nonn,base,fini,full

%O 1,1

%A _G. L. Honaker, Jr._ and _Patrick De Geest_, Nov 15 1999