-1387

Appears in sequences

• a(n) = Sum_{k=0..floor(n/2)} binomial(n - k*(k-1)/2, k).at n=14A064188
• Matrix inverse of triangle A121335, where A121335(n,k) = C( n*(n+1)/2 + n-k + 1, n-k) for n>=k>=0.at n=41A121440
• The main diagonal of the array of A141425 and its higher order differences.at n=11A141516
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 433", based on the 5-celled von Neumann neighborhood.at n=25A272148