A263048 a(0)=0, a(1)=1; for n>1, a(n) = a(n-2)^a(n-1) + a(n-1)^a(n-2).

0, 1, 1, 2, 3, 17, 129145076

Offset: 0

Author

Gianmarco Giordano, Oct 08 2015

Keywords

• nonn

Comments

Next term has 365895553 digits.

Programs

Magma

[n le 2 select n-1 else Self(n-2)^Self(n-1)+Self(n-1)^Self(n-2): n in [1..7]]; // Vincenzo Librandi, Oct 09 2015

Mathematica

RecurrenceTable[{a[0] == 0, a[1] == 1, a[n] == a[n-2]^a[n-1]+a[n-1]^a[n-2]}, a, {n, 6}] (* Vincenzo Librandi, Oct 09 2015 *)
nxt[{a_,b_}]:={b,a^b+b^a}; NestList[nxt,{0,1},6][[;;,1]] (* Harvey P. Dale, May 02 2023 *)

PARI

a(n) = if(n<2, n, a(n-2)^a(n-1)+a(n-1)^a(n-2)) \\ Altug Alkan, Oct 15 2015