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(A178475(n)-6)/9.
5

%I #9 Feb 13 2013 20:24:30

%S 1371,1372,1381,1383,1392,1393,1471,1472,1491,1494,1502,1504,1581,

%T 1583,1591,1594,1613,1614,1692,1693,1702,1704,1713,1714,2371,2372,

%U 2381,2383,2392,2393,2571,2572,2601,2605,2612,2615,2681,2683,2701,2705,2723,2725

%N (A178475(n)-6)/9.

%C There are 5!=120 terms in this finite sequence. Its origin is the fact that numbers whose decimal expansion is a permutation of 12345 are all of the form 9k+6.

%H Nathaniel Johnston, <a href="/A178485/b178485.txt">Table of n, a(n) for n = 1..120</a> (full sequence)

%F a(n) + a(5!+1-n) = 7406.

%F a(n) == 1, 2, 3, 4 or 5 (mod 10).

%F a(n+6)-a(n) is an element of { 100, 110, 111, 200, 220, 222, 679 }.

%F a(n+6)-a(n) = 679 iff (n-1)%24 > 17, where % denotes the remainder upon division.

%F a(n+6)-a(n) = 200, 220 or 222 iff (n-1)%30 > 23, i.e. n==25,...,30 (mod 30).

%o (PARI) v=vector(5,i,10^(i-1))~; vecsort(vector(5!,i,numtoperm(5,i)*v))

%o is_A178475(x)= { vecsort(Vec(Str(x)))==Vec("12345") }

%o forstep( m=12345,54321,9, is_A178475(m) & print1(m","))

%Y Cf. A030298, A030299, A055089, A060117, A178486, A191819, A191820.

%K fini,full,nonn,base,easy

%O 1,1

%A _M. F. Hasler_, May 28 2010