A139105 Bisection of A139101.

1, 1001, 1001010111, 1001010111010111, 1001010111010111010111, 100101011101011101011101111101, 1001010111010111010111011111010111110111, 1001010111010111010111011111010111110111010111, 1001010111010111010111011111010111110111010111011111011111, 100101011101011101011101111101011111011101011101111101111101011111, 100101011101011101011101111101011111011101011101111101111101011111011101, 1001010111010111010111011111010111110111010111011111011111010111110111010111110111

Offset

1,2

Links

Table of n, a(n) for n=1..12.

Omar E. Pol, Determinacion geometrica de los numeros primos y perfectos.

Formula

a(n) = A139101(2n-1). - R. J. Mathar, Apr 25 2008

Maple

A139101 := proc(n) option remember ; local a, p; if n = 1 then RETURN(1); else a := 10*A139101(n-1) ; for p from ithprime(n-1)+1 to ithprime(n)-1 do a := 10*a+1 ; od: fi ; RETURN(a) ; end: A139105 := proc(n) A139101(2*n-1) ; end: seq(A139105(n), n=1..12) ; # R. J. Mathar, Apr 25 2008

Crossrefs

Cf. A139101.

Sequence in context: A143906 A215593 A204575 * A262596 A213316 A169828

Adjacent sequences: A139102 A139103 A139104 * A139106 A139107 A139108

Keyword

base,easy,nonn

Author

Omar E. Pol, Apr 08 2008

Extensions

More terms from R. J. Mathar, Apr 25 2008

Status

approved