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A287018 Primes that can be generated by the concatenation in base 2, in ascending order, of two consecutive integers read in base 10. 1
11, 37, 137, 239, 661, 727, 859, 991, 2081, 2341, 2731, 2861, 3121, 3251, 3511, 9547, 10321, 10837, 11353, 13159, 13417, 13933, 14449, 15739, 34439, 40093, 43177, 43691, 45233, 46261, 60139, 61681, 63737, 135433, 138511, 139537, 144667, 146719, 151849, 154927 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..40.

EXAMPLE

2 and 3 in base 2 are 10 and 11 and concat(10,11) = 1011 is 11 in base 10.

4 and 5 in base 2 are 100 and 101 and concat(100,101) = 100101 is 37 in base 10.

MAPLE

with(numtheory): P:= proc(q) local a, b, c, n; a:=convert(q+1, binary, decimal); b:=convert(q, binary, decimal); c:=convert(b*10^(ilog10(a)+1)+a, decimal, binary); if isprime(c) then c; fi; end: seq(P(i), i=1..1000);

MATHEMATICA

Select[Map[FromDigits[Apply[Join, IntegerDigits[#, 2]], 2] &, Partition[Range@ 320, 2, 1]], PrimeQ] (* Michael De Vlieger, May 18 2017 *)

PROG

(PARI) lista(nn) = {for (n=1, nn, if (isprime(p=fromdigits(Vec(concat(binary(n), binary(n+1))), 2)), print1(p, ", "))); } \\ Michel Marcus, May 20 2017

CROSSREFS

Cf. A000040, A030458, A287019.

Subsequence of primes of A087737.

Sequence in context: A297797 A210321 A306423 * A152094 A227412 A160623

Adjacent sequences:  A287015 A287016 A287017 * A287019 A287020 A287021

KEYWORD

nonn,base,easy

AUTHOR

Paolo P. Lava, May 18 2017

STATUS

approved

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Last modified July 22 14:31 EDT 2019. Contains 325222 sequences. (Running on oeis4.)