-1928

Appears in sequences

• Sequence is {a(4,n)}, where a(m,n) is defined at sequence A110665.at n=22A110669
• Matrix inverse of triangle A121334, where A121334(n,k) = C( n*(n+1)/2 + n-k, n-k) for n>=k>=0.at n=15A121439
• a(0) = -1 and a(n) = (-1)^(n+1)*(3*n^2 - n + 4)/2 for n >= 1.at n=36A173247
• a(1) = 1; a(n+1) = a(n) +- (sum of digits of a(1) up to a(n)), with "+" when a(n) is odd, or "-" if even.at n=38A332058