61801

Appears in sequences

• A nonsense sequence.at n=39A089075
• a(n) = (n-2)*a(n-2) + a(n-3), with a(1)=0, a(2)=1, a(3)=1.at n=13A121953
• Sp = reversal of some square s where s = x^2 for x = 1,2,.. (ignoring leading zeros). Sp is in the sequence if it is semiprime.at n=27A242097
• Number of 2Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2 or 4 neighboring 1s.at n=14A297734