A086105 Adding, multiplying and exponentiating cycle of the previous two terms similar to A039941.

0, 1, 1, 1, 1, 2, 2, 4, 6, 24, 4738381338321616896, 4738381338321616920, 22452257707354557353808363243511480320

Offset

1,6

Links

Table of n, a(n) for n=1..13.

Formula

a(1)=0, a(2)=1, a(n): if n mod 3 is 0: a(n)=a(n-2) + a(n-1), if n mod 3 is 1: a(n)=a(n-2) * a(n-1), if n mod 3 is 2: a(n)=a(n-2)^a(n-1).

Example

a(11) = a(9)^a(10)=6^24 because 11 mod 3 is 2.

Mathematica

nxt[{n_, a_, b_}]:={n+1, b, Which[Mod[n+1, 3]==0, a+b, Mod[n+1, 3]==1, a*b, True, a^b]}; NestList[ nxt, {2, 0, 1}, 12][[;; , 2]] (* Harvey P. Dale, Oct 04 2023 *)

Crossrefs

Cf. A039941.

Sequence in context: A080611 A171421 A072707 * A084701 A113815 A110946

Adjacent sequences: A086102 A086103 A086104 * A086106 A086107 A086108

Keyword

easy,nonn

Author

Anthony Peterson (civ2buf(AT)ricochet.com), Jul 09 2003

Extensions

The next 2 terms are (6^24)^((6^24)*(6^24+24)) and (6^24)^((6^24) * (6^24 + 24)) + (6^24) * (6^24 + 24).

Status

approved