

A059590


Sum of distinct factorials (0! and 1! not treated as distinct).


21



0, 1, 2, 3, 6, 7, 8, 9, 24, 25, 26, 27, 30, 31, 32, 33, 120, 121, 122, 123, 126, 127, 128, 129, 144, 145, 146, 147, 150, 151, 152, 153, 720, 721, 722, 723, 726, 727, 728, 729, 744, 745, 746, 747, 750, 751, 752, 753, 840, 841, 842, 843, 846, 847, 848, 849, 864, 865
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OFFSET

0,3


COMMENTS

Complement of A115945; A115944(a(n)) > 0; A115647 is a subsequence.  Reinhard Zumkeller, Feb 02 2006
A115944(a(n)) = 1. [Reinhard Zumkeller, Dec 04 2011]
From Tilman Piesk, Jun 04 2012: (Start)
The inversion vector (compare A007623) of finite permutation a(n) (compare A055089, A195663) has only zeros and ones. Interpreted as a binary number it is 2*n (or n when the inversion vector is defined without the leading 0).
The inversion set of finite permutation a(n) interpreted as a binary number (compare A211362) is A211364(n).
(End)


LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..500
Index entries for sequences related to factorial numbers


FORMULA

G.f. 1/(1x) * sum(k>=0, (k+1)!x^2^k/(1+x^2^k)).  Ralf Stephan, Jun 24 2003
a(n)=Sum_k>=0 {A030308(n,k)*A000142(k+1)}.  From Philippe Deléham, Oct 15 2011.


EXAMPLE

128 is in the sequence since 5!+3!+2!=128


MAPLE

[seq(bin2facbase(j), j=0..64)]; bin2facbase := proc(n) local i; add((floor(n/(2^i)) mod 2)*((i+1)!), i=0..floor_log_2(n)); end;
floor_log_2 := proc(n) local nn, i; nn := n; for i from 1 to n do if(0 = nn) then RETURN(i); fi; nn := floor(nn/2); od; end;


MATHEMATICA

a[n_] := Reverse[id = IntegerDigits[n, 2]].Range[Length[id]]!; Table[a[n], {n, 0, 60}] (* JeanFrançois Alcover, Jun 19 2012, after Philippe Deléham *)


PROG

(Haskell)
import Data.List (elemIndices)
a059590 n = a059590_list !! n
a059590_list = elemIndices 1 $ map a115944 [0..]
 Reinhard Zumkeller, Dec 04 2011


CROSSREFS

Cf. A014597, A051760, A051761, A059589, A060112 (sums of distinct nonconsecutive factorials). Subset of A060132.
Other sequences that are built by replacing 2^k in the binary representation with other numbers: A029931 (naturals), A089625 (primes), A022290 (Fibonacci).
Cf. A025494 (subsequence).
Sequence in context: A255527 A060132 A257262 * A144705 A028733 A028789
Adjacent sequences: A059587 A059588 A059589 * A059591 A059592 A059593


KEYWORD

nonn


AUTHOR

Henry Bottomley, Jan 24 2001


STATUS

approved



