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%I #11 Nov 20 2019 07:52:35
%S 1,2,3,5,7,11,13,17,23,31,37,41,43,47,53,61,67,71,73,83,97,101,103,
%T 107,113,131,137,167,173,197,211,223,241,271,283,307,311,313,317,331,
%U 337,347,353,367,373,383,397,401,431,443,461,467,503,523,541,547,571,601
%N Numbers in which every suffix (in base 10) is 1 or a prime.
%C Subsequence of A042986 apart from first term; a(n+1)=A042986(n) for n<25.
%H Reinhard Zumkeller, <a href="/A143390/b143390.txt">Table of n, a(n) for n = 1..1000</a>
%t prQ[n_] := n == 1 || PrimeQ[n];
%t okQ[n_] := Module[{dd = IntegerDigits[n]}, AllTrue[Range[Length[dd]-1], prQ@ FromDigits@ Drop[dd, #]&]];
%t {1}~Join~Select[ Prime@Range[1000], okQ] (* _Jean-François Alcover_, Nov 20 2019 *)
%o (PARI) is(n)=my(d=digits(n,10)); for(i=1,#d-1, if(!isprime(fromdigits(d[i..#d],10)), return(0))); isprime(d[#d]) || d[#d]==1 \\ _Charles R Greathouse IV_, Nov 26 2016
%Y Cf. A012883, A012884.
%K nonn,base
%O 1,2
%A _Reinhard Zumkeller_, Aug 13 2008
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