login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A127986 Numbers of the form n! + 2^n - 1. 8
2, 5, 13, 39, 151, 783, 5167, 40575, 363391, 3629823, 39918847, 479005695, 6227028991, 87178307583, 1307674400767, 20922789953535, 355687428227071, 6402373705990143, 121645100409356287, 2432902008177688575 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

REFERENCES

F. Luca, I.E. Shparlinsky, 2005. On the largest prime factor of n! + 2n - 1. J. Th. des Nombres de Bordeaux Vol.17, Fasc. 3

LINKS

Bosma W. On the largest prime factor of n! + 2n - 1.

FORMULA

a(n) = n! + 2^n - 1

MATHEMATICA

Table[n! + 2^n - 1, {n, 1, 30}] (*Artur Jasinski*)

PROG

(Other) sage: [gaussian_binomial(n, 1, 2)+factorial(n) for n in xrange(1, 21)] # [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), May 29 2009]

CROSSREFS

Cf. A127987.

Sequence in context: A149861 A148305 A104447 * A133448 A149862 A149863

Adjacent sequences:  A127983 A127984 A127985 * A127987 A127988 A127989

KEYWORD

nonn

AUTHOR

Artur Jasinski (grafix(AT)csl.pl), Feb 09 2007

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 17 14:50 EST 2012. Contains 206050 sequences.