100410

Appears in sequences

• Number of squares (of another matrix) in the group GL(2,Z_n) described in sequence A000252.at n=23A068516
• a(n) = 20 + floor( (1 + Sum_{j=1..n-1} a(j)) / 2 ).at n=21A120145
• a(n) is the number of integers that can be represented in a 7-segment display by using only n segments (version A006942).at n=23A350437