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A077718
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Primes which can be expressed as sum of distinct powers of 4.
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13
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5, 17, 257, 277, 337, 1093, 1109, 1297, 1301, 1361, 4177, 4357, 4373, 4421, 5189, 5381, 5393, 5441, 16453, 16657, 16661, 17477, 17489, 17669, 17681, 17729, 17749, 20549, 20753, 21521, 21569, 21589, 21841, 65537, 65557, 65617, 65809, 66629
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OFFSET
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1,1
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COMMENTS
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Primes whose base 4 representation contains only zeros and 1's.
As a subsequence of primes in A000695, these could be called Moser-de Bruijn primes. See also A235461 for those terms whose base 4 representation also represents a prime in base 2. - M. F. Hasler, Jan 11 2014
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LINKS
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MAPLE
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f:= proc(n) local L, x;
L:= convert(n, base, 2);
x:= 1+add(L[i]*4^i, i=1..nops(L));
if isprime(x) then x fi
end proc:
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MATHEMATICA
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Select[Prime[Range[6650]], Max[IntegerDigits[#, 4]]<=1&] (* Jayanta Basu, May 22 2013 *)
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PROG
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(PARI) for(i=1, 999, isprime(b=vector(#b=binary(i), j, 4^(#b-j))*b~)&&print1(b", ")) \\ - M. F. Hasler, Jan 12 2014
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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