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%I #19 May 31 2015 16:45:30
%S 11,78,698,12280,179685,5518135,1037845296,1037845296,46935813565,
%T 2860727439460,285947759601954,1018897102759406,672654273047783383
%N Least number that is pandigital in some base >= n but not pandigital in bases 3 through n-1.
%C Gives an upper bound on the testing needed to check membership in A239348.
%H Charles R Greathouse IV, <a href="/A239437/a239437.gp.txt">GP script for computing terms</a>
%F Trivially a(n) >= A049363(n) > n^(n-1).
%o (PARI) See Greathouse link.
%o (Python)
%o from itertools import permutations
%o from gmpy2 import digits
%o def A239437(n): # requires 3 <= n <= 62
%o ....m = n
%o ....while True:
%o ........s = ''.join([digits(i,m) for i in range(m)])
%o ........for d in permutations(s,m):
%o ............if d[0] != '0':
%o ................c = mpz(''.join(d),m)
%o ................for b in range(3,n):
%o ....................if len(set(digits(c,b))) == b:
%o ........................break
%o ................else:
%o ....................return int(c)
%o ........m += 1 # _Chai Wah Wu_, May 31 2015
%Y Subsequence of A154314. Cf. A239348.
%K nonn,base,hard
%O 3,1
%A _Charles R Greathouse IV_, Mar 18 2014
%E a(15) from _Giovanni Resta_, Mar 19 2014
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