cp's OEIS Frontend

A257893 Pandigital numbers reordered so that the numbers A050278(n)/2^k, where 2^k||A050278(n), appear in nondecreasing order.

%I A257893 #14 May 22 2025 10:21:43
%S A257893 3076521984,3718250496,6398410752,1384906752,2769813504,2845310976,
%T A257893 1578369024,1074659328,4761059328,9805234176,2507931648,1294073856,
%U A257893 5619843072,6591873024,9073852416,9574023168,1208549376,1249837056,6103498752,1542389760,1683947520
%N A257893 Pandigital numbers reordered so that the numbers A050278(n)/2^k, where 2^k||A050278(n), appear in nondecreasing order.
%C A257893 If two such numbers A050278(n_1)/2^k_1 and A050278(n_2)/2^k_2 are equal, then A050278(n_1) appears earlier than A050278(n_2) iff  A050278(n_1)<A050278(n_2). For example, a(4)/2^18=a(5)/2^19=5283.
%C A257893 There are 184423 such pairs.
%H A257893 Chai Wah Wu, <a href="/A257893/b257893.txt">Table of n, a(n) for n = 1..1000</a>
%F A257893 min(A050278(n)/2^k) = 3076521984/2^21 = 1467.
%o A257893 (Python)
%o A257893 from itertools import permutations
%o A257893 l = []
%o A257893 for d in permutations('0123456789', 10):
%o A257893     if d[0] != '0':
%o A257893         d2 = int(''.join(d))
%o A257893         d = d2
%o A257893         r = d2 % 2
%o A257893         while not r:
%o A257893             d2, r = divmod(d2, 2)
%o A257893         l.append((d2,d))
%o A257893 l.sort()
%o A257893 A257893_list = [b for a,b in l] # _Chai Wah Wu_, May 24 2015
%Y A257893 Cf. A050278.
%K A257893 nonn,base,fini
%O A257893 1,1
%A A257893 _Vladimir Shevelev_ and _Peter J. C. Moses_, May 12 2015