Number of n-step three-sided prudent self-avoiding walks ending on the left side of their box.

Terms

a(0) =1a(1) =3a(2) =7a(3) =18a(4) =45a(5) =114a(6) =286a(7) =721a(8) =1812a(9) =4558a(10) =11449a(11) =28757a(12) =72172a(13) =181074a(14) =454043a(15) =1138082a(16) =2851369a(17) =7141220a(18) =17878222a(19) =44743249a(20) =111939780a(21) =279966725a(22) =700000634a(23) =1749720020a(24) =4372423409a(25) =10923598469a(26) =27283760095a(27) =68130718351a(28) =170093054202