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A281257
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Primes in A067894: primes in the partial sums of the binary representations of the first m natural numbers, reading these representations in decimal.
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1
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11, 223, 2556997, 3333331, 14559007, 47836783, 56672227, 65555671, 181114559, 411488881, 583227779, 1399999987, 5723503439, 10047846871, 11361255547, 13787777879, 18474111311, 19905449987, 20235780199, 21226777753, 22557892319, 71445725647, 83447001413, 103459003423
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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0 + 1 + 10 = 11 (prime), so 11 is in the sequence.
0 + 1 + 10 + 11 + 100 + 101 = 223 (prime), so 223 is in the sequence.
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MAPLE
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select(isprime, ListTools:-PartialSums(map(convert, [$1..1000], binary))); # Robert Israel, Jan 18 2017
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MATHEMATICA
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Select[Accumulate[Table[FromDigits[IntegerDigits[n, 2]], {n, 0, 1000}]], PrimeQ]
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PROG
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(PARI) F(k, {b=10})=sum(i=1, k, subst(Pol(binary(i), y), y, b));
test(k, {b=10})={my(z=F(k, b)); return(isprime(z)*z)};
Values(n, {b=10})={my(L=List(), j, t); while(#L<n, t=test(j++, b); if(t, listput(L, j))); return(vector(#L, i, L[i]))}
firstTerms(n, {b=10})={my(w=Values(n, b)); return(vector(#w, i, F(w[i], b)))} \\ Example: print(firstTerms(25)); - R. J. Cano, Jan 19 2017
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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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