Number of unrooted Eulerian maps with bicolored faces which are self-isomorphic under reversing the colors.

A090375

Number of unrooted Eulerian maps with bicolored faces which are self-isomorphic under reversing the colors.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =4a(4) =8a(5) =17a(6) =40a(7) =93a(8) =224a(9) =538a(10) =1344a(11) =3352a(12) =8448a(13) =21573a(14) =54912a(15) =143037a(16) =366080a(17) =968083a(18) =2489344a(19) =6664856a(20) =17199104a(21) =46515759a(22) =120393728a(23) =328382874a(24) =852017152a(25) =2340706462a(26) =6085836800a(27) =16822999572a(28) =43818024960a(29) =121777594508

External references