OFFSET
1,2
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
1*2+1=3
3*2+1=7
7*2+1=15
15*2+2=3
etc.
MATHEMATICA
a[1] = 1; a[n_] := a[n] = 2a[n - 1] + Floor[Log[10, a[n - 1]]] + 1 (* Robert G. Wilson v, Apr 20 2006 *)
RecurrenceTable[{a[1]==1, a[n]==2a[n-1]+IntegerLength[a[n-1]]}, a[n], {n, 40}] (* Harvey P. Dale, May 03 2011 *)
NestList[2#+IntegerLength[#]&, 1, 30] (* Harvey P. Dale, Oct 01 2012 *)
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
Zededarian Zee (Zededarian(AT)Gmail.com), Apr 19 2006
EXTENSIONS
More terms from Stefan Steinerberger, Jonathan Vos Post, Robert G. Wilson v and James Greene (jmg482(AT)psu.edu), Apr 20 2006. Also from Atilla Bora (borabanana(AT)gmail.com), Apr 23 2006
STATUS
approved