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A318779
Smallest n-th power that is pandigital in base n.
2
4, 64, 625, 248832, 11390625, 170859375, 1406408618241, 3299763591802133, 3656158440062976, 550329031716248441, 766217865410400390625, 15791096563156692195651, 6193386212891813387462761, 243008175525757569678159896851, 3433683820292512484657849089281
OFFSET
2,1
COMMENTS
For the corresponding n-th roots a(n)^(1/n), see A318780.
LINKS
FORMULA
a(n) = A318780(n)^n.
EXAMPLE
a(2)=4 because 1^2 = 1 = 1_2 (not pandigital in base 2, since it contains no 0 digit), but 2^2 = 4 = 100_2.
a(3)=64 because 1^3 = 1 = 1_3, 2^3 = 8 = 22_3, and 3^3 = 27 = 1000_3 are all nonpandigital in base 3, but 4^3 = 64 = 2101_3.
a(16) = 81^16 = 3433683820292512484657849089281 = 2b56d4af8f7932278c797ebd01_16.
PROG
(Python)
from itertools import count
from sympy import integer_nthroot
from sympy.ntheory import digits
def A318779(n): return next(k for k in (k**n for k in count(integer_nthroot((n**n-n)//(n-1)**2+n**(n-2)*(n-1)-1, n)[0])) if len(set(digits(k, n)[1:]))==n) # Chai Wah Wu, Mar 13 2024
CROSSREFS
Cf. A049363 (smallest pandigital number in base n), A185122 (smallest pandigital prime in base n), A260182 (smallest square that is pandigital in base n), A260117 (smallest triangular number that is pandigital in base n), A318725 (smallest k such that k! is pandigital in base n), A318780 (smallest k such that k^n is pandigital in base n).
Sequence in context: A224446 A128782 A353453 * A264567 A264575 A053957
KEYWORD
nonn,base
AUTHOR
Jon E. Schoenfield, Sep 03 2018
STATUS
approved