Doubles (index 2+) under "EGJ" (unordered, element, labeled) transform.

A032320

Doubles (index 2+) under "EGJ" (unordered, element, labeled) transform.

Terms

    a(0) =2a(1) =2a(2) =12a(3) =126a(4) =1800a(5) =33540a(6) =757680a(7) =20149290a(8) =616940520a(9) =21378058800a(10) =827126546400

External references