Number of mutual-visibility sets in the n-sun graph.

Terms

a(0) =4a(1) =13a(2) =42a(3) =135a(4) =448a(5) =1505a(6) =5078a(7) =17163a(8) =58044a(9) =196341a(10) =664194a(11) =2246927a(12) =7601272a(13) =25714889a(14) =86992814a(15) =294294547a(16) =995591284a(17) =3368061149a(18) =11394069210a(19) =38545859991a(20) =130399710256a(21) =441139059889