Number of 10 X 2 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 10 zero-sum 2-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).

A192711

Number of 10 X 2 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 10 zero-sum 2-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).

Terms

    a(0) =2a(1) =6a(2) =19a(3) =49a(4) =118a(5) =259a(6) =534a(7) =1042a(8) =1941a(9) =3465a(10) =5996a(11) =10040a(12) =16364a(13) =26012a(14) =40522a(15) =61835a(16) =92657a(17) =136556a(18) =198316a(19) =283977a(20) =401349a(21) =560438a(22) =774140a(23) =1058263a(24) =1432174a(25) =1920672a(26) =2554179a(27) =3369134a(28) =4409927a(29) =5730887

External references