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A024781 Every suffix prime and no 0 digits in base 6 (written in base 6).

%I A024781 #17 Apr 27 2022 13:34:29
%S A024781 2,3,5,15,25,35,45,115,125,135,215,225,245,335,345,435,445,515,525,
%T A024781 1115,1125,1245,1335,1345,1435,1445,2115,2135,2225,2335,2345,2435,
%U A024781 3125,3445,3515,4115,4215,4225,4435,4525,5215,5245,5345,5525,11115,11245,12135
%N A024781 Every suffix prime and no 0 digits in base 6 (written in base 6).
%C A024781 The final term is a(454) = 14141511414451435.
%H A024781 Nathaniel Johnston, <a href="/A024781/b024781.txt">Table of n, a(n) for n = 1..454</a> (full sequence)
%p A024781 a:=[[2], [3], [5]]: b:=[]: l1:=1: l2:=5: do for j from l1 to l2 do for k from 1 to 5 do d:=[op(a[j]),k]: if(isprime(op(convert(d, base, 6, 6^nops(d)))))then a:=[op(a), d]: fi: od: od: l1:=l2+1: l2:=nops(a): if(l1>l2)then break: fi: od: for j from 1 to nops(a) do b:=[op(b),op(convert(a[j], base, 10, 10^nops(a[j])))]: od: b:=sort(b): seq(b[j],j=1..nops(b)); # _Nathaniel Johnston_, Jun 21 2011
%o A024781 (Python)
%o A024781 from sympy import isprime
%o A024781 def afull():
%o A024781     prime_strings, alst = list("235"), []
%o A024781     while len(prime_strings) > 0:
%o A024781         alst.extend(sorted(int(p) for p in prime_strings))
%o A024781         candidates = set(d+p for p in prime_strings for d in "12345")
%o A024781         prime_strings = [c for c in candidates if isprime(int(c, 6))]
%o A024781     return alst
%o A024781 print(afull()) # _Michael S. Branicky_, Apr 27 2022
%Y A024781 Cf. A024779, A024780, A024781, A024782, A024783, A024784, A024785
%K A024781 nonn,base,easy,fini,full
%O A024781 1,1
%A A024781 _David W. Wilson_