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A178478 Permutations of 12345678: Numbers having each of the decimal digits 1..8 exactly once, and no other digit. 4
12345678, 12345687, 12345768, 12345786, 12345867, 12345876, 12346578, 12346587, 12346758, 12346785, 12346857, 12346875, 12347568, 12347586, 12347658, 12347685, 12347856, 12347865, 12348567, 12348576, 12348657, 12348675, 12348756, 12348765 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

It would be nice to have a simple explicit formula for the n-th term.

An efficient procedure for generating the n-th term of this sequence can be found at A178475. - Nathaniel Johnston, May 19 2011

LINKS

Nathaniel Johnston, Table of n, a(n) for n = 1..10000

MATHEMATICA

Take[FromDigits/@Permutations[Range[8]], 40] (* Harvey P. Dale, Oct 29 2014 *)

PROG

(PARI) is_A178478(x)= { vecsort(Vec(Str(x)))==Vec("12345678") }

(PARI) A178478(n)={my(b=vector(7, k, 1+(n-1)%(k+1)!\k!), t=b[7], d=vector(7, i, i+(i>=t))); for(i=1, 6, t=10*t+d[b[7-i]]; d=vecextract(d, Str("^"b[7-i]))); t*10+d[1]} \\ - M. F. Hasler (following N. Johnston's comment), Jan 10 2012

CROSSREFS

Cf. A030298, A030299, A055089, A060117, A178475-A178477, A191820.

Sequence in context: A247831 A161592 A164338 * A077302 A070189 A178069

Adjacent sequences:  A178475 A178476 A178477 * A178479 A178480 A178481

KEYWORD

fini,nonn,easy,base

AUTHOR

M. F. Hasler, Oct 09 2010

STATUS

approved

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Last modified August 21 17:55 EDT 2017. Contains 290893 sequences.