42541

Appears in sequences

• Denominators of continued fraction convergents to sqrt(131).at n=7A041239
• Denominators of continued fraction convergents to sqrt(524).at n=13A042003
• Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 2X3 U in any orientation.at n=9A146062
• Number of 2 X 2 0..n arrays with rows and columns in lexicographically nondecreasing order.at n=17A229795