Row sums of a number triangle related to the Pell numbers.

Terms

a(0) =1a(1) =-1a(2) =-5a(3) =-11a(4) =-19a(5) =-29a(6) =-41a(7) =-55a(8) =-71a(9) =-89a(10) =-109a(11) =-131a(12) =-155a(13) =-181a(14) =-209a(15) =-239a(16) =-271a(17) =-305a(18) =-341a(19) =-379a(20) =-419a(21) =-461a(22) =-505a(23) =-551a(24) =-599a(25) =-649a(26) =-701a(27) =-755a(28) =-811a(29) =-869