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A329875
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a(1) = 1, for n > 0, a(n+1) is the least prime number > a(n) whose binary expansion ends with the binary expansion of a(n).
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1
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1, 3, 7, 23, 151, 919, 8087, 90007, 2449303, 6643607, 115695511, 786784151, 2934267799, 183322894231, 1007956615063, 4306491498391, 101063514742679, 2634338305138583, 106217129734659991, 2267944950872498071, 69137392218069622679, 2504107609947730435991
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OFFSET
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1,2
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COMMENTS
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This sequence is a binary variant of A053582.
Dirichlet's theorem on arithmetic progressions guaranties that this sequence is infinite.
We can build a similar sequence for any base b > 1 and any starting value coprime to b.
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LINKS
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EXAMPLE
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The first terms, alongside their binary representations, are:
n a(n) bin(a(n))
- ------- ----------------------
1 1 1
2 3 11
3 7 111
4 23 10111
5 151 10010111
6 919 1110010111
7 8087 1111110010111
8 90007 10101111110010111
9 2449303 1001010101111110010111
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PROG
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(PARI) print1 (v=1); for (n=2, 22, forstep (w=v+s=(b=2)^#digits(v, b), oo, s, if (isprime(w), print1 (", "v=w); break)))
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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