-10900

Appears in sequences

• A coefficients of characteristic polynomials of A_n Cartan matrices times their transposes: t(n,m,d)=If[ n == m, 2, If[n == m - 1 || n == m + 1, -1, 0]]. M(d)=t(n,m,d)*Transpose[t(n,m,d)].at n=31A158199
• Alternating sum of heptagonal pyramidal numbers.at n=29A269428