A138711 n-th run has length n-th positive triangular number, with digits 0 and 1 only, starting with 1.

1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1

Offset

1,1

Links

Table of n, a(n) for n=1..84.

Example

.n ..... Run ............................... Length
.1 ..... 1 ................................. 1
.2 ..... 0,0,0 ............................. 3
.3 ..... 1,1,1,1,1,1........................ 6
.4 ..... 0,0,0,0,0,0,0,0,0,0 ............... 10
.5 ..... 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1 ..... 15

Mathematica

Flatten[Table[Join[PadRight[{}, (n(n+1))/2, 1], PadRight[{}, ((n+1)(n+2))/2, 0]], {n, 1, 7, 2}]] (* Harvey P. Dale, Dec 11 2011 *)

Crossrefs

Cf. A000217, A057211, A138149, A138709.

Sequence in context: A004555 A200261 A288855 * A285617 A246500 A185114

Adjacent sequences: A138708 A138709 A138710 * A138712 A138713 A138714

Keyword

easy,nonn

Author

Omar E. Pol, Mar 29 2008

Status

approved