20938

Appears in sequences

• Number of base 18 circular n-digit numbers with adjacent digits differing by 3 or less.at n=5A125328
• Positions of 11's in A131744.at n=11A133152
• Number of (n+2) X (2+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 3 5 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 3 5 6 or 7.at n=17A252378
• a(n) = 3*n^3 + n^2.at n=19A294315
• Expansion of Sum_{k>0} x^k/(1 - k*x^k)^3.at n=20A363642