A080809 a(1) = 6; thereafter, a(n)= smallest n-th power obtained by inserting digits anywhere in a(n-1).

6, 16, 216, 2085136, 62019685191371643, 82626753081964483505319130781618465733184

Offset: 1

Author

Amarnath Murthy, Mar 22 2003

Keywords

• nonn
• base

Crossrefs

Cf. A080804, A080805, A080806, A080807, A080808, A080810, A080811, A080812.

Programs

Maple

buffedStr := proc(n,candid) local f ; if length(n) = 0 then RETURN(true) ; fi ; f := SearchText(substring(n,1),candid) ; if f = 0 then RETURN(false) ; else if buffedStr(substring(n,2..-1),substring(candid,f+1..-1)) = true then RETURN(true) ; else RETURN(false) ; fi ; fi ; end: A080809 := proc(preva,n) local i,tst ; i := 1 ; while true do tst := i^n; if buffedStr(convert(preva,string),convert(tst,string)) = true then RETURN(tst) ; fi ; i := i+1 ; od: end: an :=6 ; for n from 2 to 15 do an := A080809(an,n) ; end ; # R. J. Mathar, Sep 20 2006

Formula

a(n)=A080514(n), n>1. - R. J. Mathar, Sep 18 2008

Extensions

More terms from R. J. Mathar, Sep 20 2006

Copied a term from A080514. - Sean A. Irvine, Sep 01 2009