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A024784 Every suffix prime and no 0 digits in base 9 (written in base 9).

%I A024784 #22 Apr 27 2022 13:54:09
%S A024784 2,3,5,7,12,25,32,45,47,52,65,67,87,212,232,267,287,425,432,447,465,
%T A024784 625,667,812,832,847,867,887,2287,2432,4212,4465,4667,4832,4847,4887,
%U A024784 6212,6267,6425,6832,6887,8287,8447,8667,8812,22287,24465,24847,26212,26887
%N A024784 Every suffix prime and no 0 digits in base 9 (written in base 9).
%C A024784 The final term of the sequence is a(108) = 4284484465.
%H A024784 Nathaniel Johnston, <a href="/A024784/b024784.txt">Table of n, a(n) for n = 1..108</a> (full sequence)
%p A024784 a:=[[2],[3],[5],[7]]: l1:=1: l2:=4: do for k from 1 to 8 do for j from l1 to l2 do d:=[op(a[j]),k]: if(isprime(op(convert(d, base, 9, 9^nops(d)))))then a:=[op(a), d]: fi: od: od: l1:=l2+1: l2:=nops(a): if(l1>l2)then break: fi: od: seq(op(convert(a[j], base, 10, 10^nops(a[j]))), j=1..nops(a)); # _Nathaniel Johnston_, Jun 21 2011
%o A024784 (Python)
%o A024784 from sympy import isprime
%o A024784 def afull():
%o A024784     prime9strings, alst = list("2357"), []
%o A024784     while len(prime9strings) > 0:
%o A024784         alst.extend(sorted(int(p) for p in prime9strings))
%o A024784         candidates = set(d+p for p in prime9strings for d in "12345678")
%o A024784         prime9strings = [c for c in candidates if isprime(int(c, 9))]
%o A024784     return alst
%o A024784 print(afull()) # _Michael S. Branicky_, Apr 27 2022
%Y A024784 Cf. A024779, A024780, A024781, A024782, A024783, A024785.
%K A024784 nonn,base,easy,fini,full
%O A024784 1,1
%A A024784 _David W. Wilson_