A091782 a(1) = 1, a(2) = 1, a(3) = a(1) + concatenation a(1), a(2). In general a(n) = a(1) + a(1)a(2)+ a(1)a(2)a(3) + ... + a(1)a(2)...a(n-1), where a(1)a(2)...a(r) is the concatenation of first r terms.

1, 1, 12, 1124, 11122248, 1112112422244496, 11121124111222482224224844488992, 1112112411122248111211242224449622242248222444964448449688977984

Offset

1,3

Links

Table of n, a(n) for n=1..8.

Formula

a(n) = concat(a(1), ..., a(n-1)) + a(n-1). - Charles R Greathouse IV, Mar 30 2004

Example

a(3) = 1+11 = 12.

Crossrefs

Cf. A091781.

Sequence in context: A004073 A109229 A112457 * A291952 A112580 A229691

Adjacent sequences: A091779 A091780 A091781 * A091783 A091784 A091785

Keyword

base,nonn

Author

Amarnath Murthy, Feb 17 2004

Extensions

More terms from Charles R Greathouse IV, Mar 30 2004

Status

approved