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A213619
Let m be the n-th hyperoperation applied to n (see A189896). a(n) is the m-th hyperoperation applied to n and m.
1
OFFSET
0,2
COMMENTS
Let bn=A189896(n), that is, bn=H_n(n,n), where H_n is the n-th hyperoperation.
Then
a(n) = H_bn(n,bn), hence
a(0) = H_b0(0,b0) = H_1(0,1) = 0+1 = 1,
a(1) = H_b1(1,b1) = H_2(1,2) = 1*2 = 2,
a(2) = H_b2(2,b2) = H_4(2,4) = 2^2^2^2 = 65536, and
a(3) is too large to include here.
FORMULA
a(n) = H_H_n(n,n)(n,H_n(n,n)).
EXAMPLE
a(0) = H_H_0(0,0)(0,H_0(0,0)) = H_1(0,1) = 0+1 = 1.
a(1) = H_H_1(1,1)(1,H_1(1,1)) = H_2(1,1+1) = 1*(1+1) = 2.
a(2) = H_H_2(2,2)(2,H_2(2,2)) = H_4(2,2*2) = H_3(2,H_3(2,H_3(2,2))) = 2^2^2^2 = 2^2^4 = 2^16 = 65536.
CROSSREFS
Cf. A189896.
Sequence in context: A306907 A052427 A051833 * A060895 A100266 A272137
KEYWORD
nonn,bref
AUTHOR
Jens Ahlström, Jun 16 2012
STATUS
approved