A159305 Sequence of happy tribonacci numbers.

1, 7, 13, 44, 98950096, 15832480722303616, 1127444240280152749, 80286250603180403871, 271606440286606849984, 3108406708580377597810, 120346786571258131649185, 1682555786678552786861430747564

Offset

1,2

Comments

Intersection of A000073 and A007770. - Michel Marcus, Aug 08 2013

Links

G. C. Greubel, Table of n, a(n) for n = 1..550

Mathematica

hapQ[n_]:=MemberQ[NestList[Total[IntegerDigits[#]^2]&, n, 15], 1]; Select[ LinearRecurrence[{1, 1, 1}, {1, 1, 2}, 150], hapQ] (* Harvey P. Dale, Jun 05 2011 *)

Crossrefs

Sequence in context: A272032 A023286 A287685 * A146648 A374727 A219501

Adjacent sequences: A159302 A159303 A159304 * A159306 A159307 A159308

Keyword

nonn,base

Author

Levrand Roland (roland.levrand(AT)gmx.ch), Apr 09 2009

Status

approved