|
| |
|
|
A159305
|
|
Sequence of happy tribonacci numbers.
|
|
1
|
|
|
|
1, 7, 13, 44, 98950096, 15832480722303616, 1127444240280152749, 80286250603180403871, 271606440286606849984, 3108406708580377597810, 120346786571258131649185, 1682555786678552786861430747564
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
COMMENTS
|
|
|
|
LINKS
|
|
|
|
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
|
|
|
|
KEYWORD
|
nonn,base
|
|
|
AUTHOR
|
Levrand Roland (roland.levrand(AT)gmx.ch), Apr 09 2009
|
|
|
STATUS
|
approved
|
| |
|
|
