A015498 a(0)=1, a(1)=10, a(n) = sum_{k=0}^{k=n-1} 10^k a(k).

1, 10, 101, 10201, 10211201, 102122221201, 10212324242321201, 10212334454645443321201, 102123354758788887857453321201, 10212335578002243544534219977553321201

Offset

0,2

Links

Table of n, a(n) for n=0..9.

Formula

a(n) = (10^(n-2) + 1) * a(n-1). - Vincenzo Librandi, Nov 11 2012

Prog

(Magma) I:=[1, 10, 101]; [n le 3 select I[n] else (10^(n-2)+1)*Self(n-1): n in [1..15]]; // Vincenzo Librandi, Nov 11 2012

Crossrefs

Sequence in context: A041182 A036299 A061107 * A266283 A309540 A039393

Adjacent sequences: A015495 A015496 A015497 * A015499 A015500 A015501

Keyword

nonn,easy

Author

Olivier Gérard

Status

approved