A266205 a(n) = G_n(6), where G is the Goodstein function defined in A266201.
6, 29, 257, 3125, 46655, 98039, 187243, 332147, 555551, 885775, 1357259, 2011162, 2895965, 4068068, 5592391, 7542974, 10003577, 13068280, 16842083, 21441506, 26995189, 33644492, 41544095, 50862597, 61783119, 74503901, 89238903, 106218405, 125689607, 147917229
Offset: 0
Examples
G_1(6) = B_2(6) - 1 = B_2(2^2 + 2) - 1 = 3^3 + 3 - 1 = 29; G_2(6) = B_3(G_1(6)) - 1 = B_3(3^3 + 2) - 1 = 4^4 + 2 - 1 = 257; G_3(6) = B_4(G_2(6)) - 1 = 5^5 + 1 - 1 = 3125; G_4(6) = B_5(G_3(6)) - 1 = 6^6 - 1 = 46655; G_5(6) = B_6(G_4(6)) - 1 = 5*7^5 + 5*7^4 + 5*7^3 + 5*7^2 + 5*7 + 5 - 1 = 98039.
Links
- Nicholas Matteo, Table of n, a(n) for n = 0..10000
- R. L. Goodstein, On the Restricted Ordinal Theorem, The Journal of Symbolic Logic 9, no. 2 (1944), 33-41.
- Wikipedia, Goodstein sequence
Crossrefs
Programs
-
PARI
lista(nn) = {print1(a = 6, ", "); for (n=2, nn, pd = Pol(digits(a, n)); q = sum(k=0, poldegree(pd), if (c=polcoeff(pd, k), c*x^subst(Pol(digits(k, n)), x, n+1), 0)); a = subst(q, x, n+1) - 1; print1(a, ", "););} \\ Michel Marcus, Feb 22 2016