cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A139107 Bisection of A139102.

Original entry on oeis.org

1, 9, 599, 38359, 2454999, 628479869, 643563386359, 41188056726999, 168706280353789919, 43188807770570219359, 2764083697316494039005, 2830421706052089895941623, 46373629231957440855107559295
Offset: 1

Views

Author

Omar E. Pol, Apr 08 2008

Keywords

Crossrefs

Cf. A139102.

Programs

  • 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: bin2dec := proc(n) local nshft ; nshft := convert(n,base,10) ; add(op(i,nshft)*2^(i-1),i=1..nops(nshft) ) ; end: A139102 := proc(n) bin2dec(A139101(n)) ; end: A139107 := proc(n) A139102(2*n-1) ; end: seq(A139107(n),n=1..35) ; # R. J. Mathar, Apr 25 2008

Extensions

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