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A024783 Every suffix prime and no 0 digits in base 8 (written in base 8).

%I A024783 #17 Apr 27 2022 13:35:31
%S A024783 2,3,5,7,13,15,23,27,35,37,45,53,57,65,73,75,123,145,153,213,227,235,
%T A024783 265,323,337,345,357,373,415,445,475,513,535,557,565,573,615,645,657,
%U A024783 673,715,723,737,753,775,1145,1153,1357,1475,1737,1775,2213,2235,2535,3123,3145
%N A024783 Every suffix prime and no 0 digits in base 8 (written in base 8).
%C A024783 The final term of the sequence is a(446) = 313636165537775.
%H A024783 Nathaniel Johnston, <a href="/A024783/b024783.txt">Table of n, a(n) for n = 1..446</a> (full sequence)
%p A024783 a:=[[2],[3],[5],[7]]: l1:=1: l2:=4: do for k from 1 to 7 do for j from l1 to l2 do d:=[op(a[j]),k]: if(isprime(op(convert(d, base, 8, 8^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 A024783 (Python)
%o A024783 from sympy import isprime
%o A024783 def afull():
%o A024783     prime_strings, alst = list("2357"), []
%o A024783     while len(prime_strings) > 0:
%o A024783         alst.extend(sorted(int(p) for p in prime_strings))
%o A024783         candidates = set(d+p for p in prime_strings for d in "1234567")
%o A024783         prime_strings = [c for c in candidates if isprime(int(c, 8))]
%o A024783     return alst
%o A024783 print(afull()) # _Michael S. Branicky_, Apr 27 2022
%Y A024783 Cf. A024779, A024780, A024781, A024782, A024784, A024785.
%K A024783 nonn,base,easy,fini,full
%O A024783 1,1
%A A024783 _David W. Wilson_