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A327701
Maximum value for base-n variant of A326344.
0
1, 20, 3, 107, 5, 310, 7, 668, 909, 1253, 11, 2082, 13, 3224, 3880, 4670, 17, 6558, 19
OFFSET
2,2
COMMENTS
For each n >= 2, let b_n(k) be the base-n A326344-like sequence defined as follows:
- b_n(1) = 1;
- b_n(k) = R_n(nextprime(b_n(k - 1))) if k is prime;
- b_n(k) = R_n(nextcompo(b_n(k - 1))) if k is composite,
where R_n(x) writes x in reverse in base n, then converts back to decimal.
a(n) is the maximum value of b_n(k) for k >= 1. All listed terms so far have been established by automating the methods of Rémy Sigrist and Andrew Weimholt in A326344.
The obvious conjecture is that a(n) = n-1 iff n-1 is 1 or an odd prime. - N. J. A. Sloane, Oct 02 2019
EXAMPLE
A326344 has a maximum value of 909, so a(10) = 909. A327241 has a maximum value of 310, so a(7) = 310.
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
STATUS
approved