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A083942
Positions of breadth-first-wise encodings (A002542) of the complete binary trees (A084107) in A014486.
2
0, 1, 8, 625, 13402696, 19720133460129649, 126747521841153485025455279433135688, 15141471069096667541622192498608408980462133134430650704600552060872705905
OFFSET
0,3
LINKS
Alexander Adamchuk, Nov 10 2007, Table of n, a(n) for n = 0..11
Eric Weisstein's World of Mathematics, Catalan Number.
FORMULA
a(n) = A057118(A084108(n)).
a(n) = A080300(A002542(n)) [provided that 2^((2^n)-1)*((2^((2^n)-1))-1) is indeed the formula for A002542].
Conjecture: a(n) = A014138(2^n-2) for n>0. - Alexander Adamchuk, Nov 10 2007
Conjecture: a(n) = Sum_{k=1..2^n-1} A000108(k). - Alexander Adamchuk, Nov 10 2007
Let h(n) = -((C(2*n,n)*hypergeom([1,1/2+n],[2+n],4))/(1+n)+I*sqrt(3)/2+1/2). Assuming Adamchuk's conjecture a(n) = h(2^n) and A014138(n) = h(n+1). - Peter Luschny, Mar 09 2015
CROSSREFS
Cf. A014138 (partial sums of Catalan numbers), A000108 (Catalan Numbers).
Sequence in context: A266317 A374142 A080320 * A274588 A027877 A129927
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 13 2003
STATUS
approved