A155698 - OEIS

A155698

a(n)=a(n-1)+a(n-2)^a(n-3); a(1)=a(2)=a(3)=1.

1, 1, 1, 2, 3, 5, 14, 139, 537963, 1005095210669462420559310863604

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OFFSET

1,4

COMMENTS

a(11) has 797 digits and is too large to include.

LINKS

FORMULA

a(n)=a(n-1)+a(n-2)^a(n-3).

EXAMPLE

a(6)=3+2^1=5.

MATHEMATICA

RecurrenceTable[{a[1]==a[2]==a[3]==1, a[n]==a[n-1]+a[n-2]^a[n-3]}, a, {n, 10}] (* Harvey P. Dale, Aug 27 2019 *)

CROSSREFS

KEYWORD

nonn

AUTHOR

Avik Roy (avik_3.1416(AT)yahoo.co.in), Jan 25 2009

STATUS

approved