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A071924
Highest m such that prime(m) divides the n-th pandigital (A050278).
1
749, 208, 6503705, 1831, 657, 1045880, 6503711, 239879, 375325, 7864, 45075, 7064, 2313602, 6503717, 59, 1766468, 78975, 840, 1046, 33355, 2133, 109, 107390, 56057, 6503758, 3386573, 6503759, 2044, 3386575, 158964, 2313623, 9463, 2313625, 36081
OFFSET
1,1
EXAMPLE
The 10th pandigital 1023457896 has prime decomposition 2^3*3^3*59*80309 and 80309 is indeed the a(10)=7864th prime, i.e., prime(7864)=80309.
MATHEMATICA
PrimePi[FactorInteger[#][[-1, 1]]]&/@(Select[Sort[FromDigits/@ Permutations[ Range[0, 9]]], IntegerLength[#]>9&, 50]) (* Harvey P. Dale, Jun 06 2018 *)
PROG
(Python)
from itertools import permutations, islice
from sympy import primepi, primefactors
def A071924(n): return primepi(max(primefactors(next(islice((int(e+''.join(d)) for e in '123456789' for d in permutations('0123456789'.replace(e, ''), 9)), n-1, None))))) # Chai Wah Wu, Dec 07 2021
CROSSREFS
Cf. A050278.
Sequence in context: A184024 A376879 A263381 * A078549 A252524 A252525
KEYWORD
nonn,base,fini
AUTHOR
Lekraj Beedassy, Jun 14 2002
EXTENSIONS
a(24)-a(33) from Donovan Johnson, Jan 25 2009
Edited by Charles R Greathouse IV, Aug 02 2010
Keyword "fini" added by Sean A. Irvine, Aug 21 2024
STATUS
approved