a(n) is the number of terms in the expansion of (x+y-z)*(x^2+y^2-z^2)*(x^3+y^3-z^3)*...*(x^n+y^n-z^n).
A086817
a(n) is the number of terms in the expansion of (x+y-z)*(x^2+y^2-z^2)*(x^3+y^3-z^3)*...*(x^n+y^n-z^n).
Terms
- a(0) =3a(1) =9a(2) =22a(3) =48a(4) =102a(5) =182a(6) =328a(7) =566a(8) =910a(9) =1396a(10) =2025a(11) =2882a(12) =3976a(13) =5304a(14) =7002a(15) =9071a(16) =11475a(17) =14444a(18) =17886a(19) =21896a(20) =26531a(21) =31880a(22) =37947a(23) =44899a(24) =52657a(25) =61500a(26) =71406a(27) =82383a(28) =94592a(29) =108097
External references
- oeis: A086817