OFFSET
0,4
FORMULA
a(n) = A002275(A000213(n)), the repunits with the property that their number of digits is a tribonacci number. - Stefan Steinerberger, Jan 27 2006
EXAMPLE
The first three terms are 1,1,1. The fourth term is 111 - which is obtained by concatenating the first three terms.
MATHEMATICA
nxt[{a_, b_, c_}]:={b, c, FromDigits[Join[Flatten[IntegerDigits/@{a, b, c}]]]}; Transpose[NestList[nxt, {1, 1, 1}, 10]][[1]] (* Harvey P. Dale, Feb 18 2013 *)
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Parthasarathy Nambi, Nov 22 2005
EXTENSIONS
More terms from Stefan Steinerberger, Jan 27 2006
STATUS
approved