A178478 Permutations of 12345678: Numbers having each of the decimal digits 1..8 exactly once, and no other digit.

12345678, 12345687, 12345768, 12345786, 12345867, 12345876, 12346578, 12346587, 12346758, 12346785, 12346857, 12346875, 12347568, 12347586, 12347658, 12347685, 12347856, 12347865, 12348567, 12348576, 12348657, 12348675, 12348756, 12348765

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