A356082 Matula-Goebel number of the complete binary tree of n levels.

1, 4, 49, 51529, 400034745289, 135016053798647886015597889

Offset: 1

Author

Kevin Ryde, Jul 26 2022

Keywords

• nonn
• more

Comments

An estimate for a(7) is 7.304058*10^55. - Hugo Pfoertner, Jul 26 2022

Examples

			For n=3, the complete binary tree of 3 levels is
        49
      /    \     a(3) = prime(4)^2
    4       4         = 49
   / \     / \
  1   1   1   1
		

Crossrefs

Cf. A006894 (Colijn-Plazzotta), A084107 (balanced binary).

Cf. A356083 (ternary), A356084 (quaternary).

Programs

PARI

a(n) = my(ret=1); for(i=2,n, ret=prime(ret)^2); ret;

Formula

a(n) = prime(a(n-1))^2, for n>=2.

Extensions

a(6) from Rémy Sigrist, Jul 26 2022