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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A256179 Sequence of power towers in ascending order, using all possible permutations of 2's and 3's.

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%I A256179 #23 Dec 23 2024 14:53:44
%S A256179 2,3,4,8,9,16,27,81,256,512,6561,19683,65536,43046721,134217728,
%T A256179 7625597484987,2417851639229258349412352,
%U A256179 443426488243037769948249630619149892803,115792089237316195423570985008687907853269984665640564039457584007913129639936
%N A256179 Sequence of power towers in ascending order, using all possible permutations of 2's and 3's.
%C A256179 a(n) is found by treating the digits of A248907(n) as power towers, so the sequence starts 2, 3, 2^2=4, 2^3=8, 3^2=9, 2^(2^2)=16, 3^3=27, 3^(2^2)=81, 2^(2^3)=256...
%H A256179 Pontus von Brömssen, <a href="/A256179/b256179.txt">Table of n, a(n) for n = 1..22</a>
%H A256179 Vladimir Reshetnikov, <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2015-March/014595.html">2-3 sequence puzzle</a>, SeqFan list, Mar 18 2015.
%F A256179 A256179 = A256229 o A248907 = A256229 o A032810 o A185969, i.e., a(n) = A256229(A248907(n)) = A256229(A032810(A185969(n))).
%F A256179 Recurrence: a(1)=2, a(2)=3, a(3)=2^2, a(4)=2^3, a(5)=3^2, a(6)=2^(2^2), a(7)=3^3, a(8)=3^(2^2), a(9)=2^(2^3), a(10)=2^(3^2), a(11)=3^(2^3), a(12)=3^(3^2); and for n>6, a(2n)=3^a(n-1), a(2n-1)=2^a(n-1). - _Vladimir Reshetnikov_, Mar 19 2015
%e A256179 a(12) = 19683 because A248907(12) = 332, and 3^(3^2) = 19683.
%e A256179 a(23) = 2^3^2^3 = 11423...73952 (1976 digits), because A248907(23) = 2323.
%o A256179 (PARI) A256179(n)=A256229(A248907[n]) \\ where A248907 is assumed to be defined as vector. - _M. F. Hasler_, Mar 19 2015
%Y A256179 Cf. A032810, A075877, A185969, A248907, A256229.
%K A256179 nonn
%O A256179 1,1
%A A256179 _Bob Selcoe_, Mar 18 2015
%E A256179 More terms from _M. F. Hasler_, Mar 19 2015