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A305497
The largest positive even integer that can be represented with n digits in base 3/2.
3
2, 4, 8, 14, 22, 34, 52, 80, 122, 184, 278, 418, 628, 944, 1418, 2128, 3194, 4792, 7190, 10786, 16180, 24272, 36410, 54616, 81926, 122890, 184336, 276506, 414760, 622142, 933214, 1399822, 2099734, 3149602, 4724404, 7086608, 10629914, 15944872, 23917310
OFFSET
1,1
LINKS
B. Chen, R. Chen, J. Guo, S. Lee et al., On Base 3/2 and its Sequences, arXiv:1808.04304 [math.NT], 2018.
FORMULA
a(n+1) = 2*floor(3*a(n)/4) + 2.
a(n) = 2*A061419(n+1) - 2.
a(n) = A305498(n+1) - 2.
a(n) = Sum_{i=0..n-1} (3/2)^i*A304274(n-i). - Alois P. Heinz, Jun 21 2018
MATHEMATICA
b[n_] := b[n] = If[n == 1, 2, Function[t, t + Mod[t, 2]][3/2 b[n - 1]]]; a[n_] := b[n + 1] - 3/2 b[n] + 1; A305497[n_] := Sum[(3/2)^i*a[n - i], {i, 0, n - 1}]; Table[A305497[n], {n, 1, 39}] (* Robert P. P. McKone, Feb 12 2021 *)
PROG
(Python)
from itertools import islice
def A305497_gen(): # generator of terms
a = 2
while True:
a += a>>1
yield (a<<1)-4
A305497_list = list(islice(A305497_gen(), 70)) # Chai Wah Wu, Sep 20 2022
KEYWORD
nonn,base
AUTHOR
Tanya Khovanova and PRIMES STEP Senior group, Jun 02 2018
STATUS
approved