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A158619 Twin prime pairs concatenated in binary representation. 1
11101, 101111, 10111101, 1000110011, 1110111111, 101001101011, 111011111101, 10001111001001, 11001011100111, 11010111101101, 1000100110001011, 1001010110010111, 1011001110110101, 1011111111000001, 1100010111000111 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Binary analog of A095958.

LINKS

Table of n, a(n) for n=1..15.

FORMULA

a(n) = A007088(A001359(n)) CONCATENATE A007088(A006512(n)) = A007088(A001359(n)) CONCATENATE A007088(A001359(n)+2).

EXAMPLE

a(1) = 11101 because 11_2 = lower of first twin prime pair = 3, and 101_2 = higher of first twin prime pair = 5.

MAPLE

A001359 := proc(n) option remember ; if n = 1 then 3; else a := nextprime(procname(n-1)) ; while not isprime(a+2) do a := nextprime(a) ; od: RETURN(a) ; fi: end: A006512 := proc(n) A001359(n)+2 ; end: A007088 := proc(n) bdgs := convert(n, base, 2) ; add( op(i, bdgs)*10^(i-1), i=1..nops(bdgs)) ; end: cat2 := proc(a, b) bdgs := max(1, 1+ilog10(b)) ; a*10^bdgs+b ; end: A158619 := proc(n) cat2(A007088(A001359(n)), A007088(A006512(n))) ; end: seq(A158619(n), n=1..30) ; # R. J. Mathar, Apr 16 2009

CROSSREFS

Cf. A001359, A006512, A007088, A045533, A095958.

Sequence in context: A204226 A235440 A235405 * A094324 A032735 A038447

Adjacent sequences:  A158616 A158617 A158618 * A158620 A158621 A158622

KEYWORD

base,easy,nonn

AUTHOR

Jonathan Vos Post, Mar 22 2009

EXTENSIONS

More terms from R. J. Mathar, Apr 16 2009

STATUS

approved

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Last modified March 25 07:12 EDT 2019. Contains 321468 sequences. (Running on oeis4.)