A131621 Sum of all n-digit Pell numbers.

8, 111, 1562, 8119, 128103, 665857, 10506008, 147830751, 768398401, 12123924128, 63018038201, 994309609247, 13990997937704, 72722761475561, 1147432427450279, 5964153172084899, 94103450048860582, 1324136026968012719, 6882627592338442563, 108595299810873229246

Offset

1,1

Links

Table of n, a(n) for n=1..20.

Example

Sum of all 1-digit Pell numbers is 8.
Sum of all 2-digit Pell numbers is 111.
Sum of all 3-digit Pell numbers is 1562.

Mathematica

With[{pnos=LinearRecurrence[{2, 1}, {0, 1}, 500]}, Table[Total[ Select[ pnos, IntegerLength[#]==n&]], {n, 20}]] (* Harvey P. Dale, Jun 13 2011 *)

Crossrefs

Cf. A000129.

Sequence in context: A020560 A144813 A079660 * A364983 A239754 A003721

Adjacent sequences: A131618 A131619 A131620 * A131622 A131623 A131624

Keyword

nonn,base

Author

Parthasarathy Nambi, Sep 01 2007

Extensions

More terms from Harvey P. Dale, Jun 13 2011

Status

approved