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A305851 a(n) = (a(n-1)+a(n-2))^(n-2) with a(1)=a(2)=1. 1
1, 1, 2, 9, 1331, 3224179360000, 348414297354956334043085401797347258376901025074126347562215651 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

a(8) has 376 digits, a(9) has 2627 digits, a(10) has 21015 digits, see b-file and a-file. - Eric Chen, Jun 14 2018

LINKS

Eric Chen, Table of n, a(n) for n = 1..9

Eric Chen, Table of n, a(n) for n = 1..10 (an a-file)

FORMULA

a(n) ~ c^((n-2)!), where c = 3.3203520468282576446980958620234685911457954899308569085994... - Vaclav Kotesovec, Jul 23 2018

MATHEMATICA

Nest[Append[#, (#[[-1]] + #[[-2]] )^(Length@ # - 2)] &, {1, 1}, 6] (* Michael De Vlieger, Jun 11 2018 *)

RecurrenceTable[{a[n] == (a[n-1] + a[n-2])^(n-2), a[1] == 1, a[2] == 1}, a, {n, 1, 7}] (* Vaclav Kotesovec, Jul 23 2018 *)

PROG

(Python)

#Generates and prints a list containing the terms, up to the term with the index of seq_limit

seq_limit=9

seq_list=[1, 1]

for seq_no in range(3, seq_limit):

....seq_list.append((seq_list[-1]+seq_list[-2])**(seq_no-2))

print(seq_list)

(PARI) a(n)=if(n<3, 1, (a(n-1)+a(n-2))^(n-2)) \\ Eric Chen, Jun 14 2018

CROSSREFS

Cf. A050923.

Sequence in context: A062840 A024226 A252584 * A208207 A229050 A221177

Adjacent sequences:  A305848 A305849 A305850 * A305852 A305853 A305854

KEYWORD

nonn,easy,less

AUTHOR

Yigithan TAMER, Jun 11 2018

STATUS

approved

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Last modified October 18 07:16 EDT 2019. Contains 328146 sequences. (Running on oeis4.)