The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A117607 Integer complexity of n represented with {1,+,!} and parentheses, where ! can be concatenated for multifactorials. 1
 1, 2, 3, 4, 5, 3, 4, 4, 5, 6, 7, 3, 4, 4, 5, 4, 5, 5, 6, 6, 4, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 3, 4, 5, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Using the set of symbols {1, +, !} and parentheses, how many 1's does it take to represent n? "!!" is double factorial, "!!!" is triple factorial and so forth. lim inf = 3, lim sup = infinity. What is the average behavior of this sequence? - Charles R Greathouse IV, Jun 15 2012 LINKS Table of n, a(n) for n=1..39. Ed Pegg, Jr., Integer Complexity Eric Weisstein's World of Mathematics, Multifactorial. Index to sequences related to the complexity of n EXAMPLE a(1) = 1 because there is one 1 in "1". a(2) = 2 because "1 + 1". a(6) = 3 because "(1+1+1)!". a(7) = 4 because "(1+1+1)!+1". a(8) = 4 because "(1+1+1+1)!!" using double factorial. a(12) = 3 because "((1+1+1)!)!!!!" using quadruple factorial. a(15) = 5 because "(1+1+1+1+1)!!" using double factorial. a(16) = 4 because "((1+1+1+1)!!)!!!!!!" using double factorial and sextuple factorial. a(24) = 3 because "(((1+1+1)!)!!!!)!!!!!!!!!!" using quadruple factorial and decuple factorial. a(36) = 3 because "(((1+1+1)!)!!!!)!!!!!!!!!" using quadruple factorial and nonuple factorial. CROSSREFS n! = A000142. n!! = A006882. n!!! = A007661. n!!!! = A007662. n!!!!! = A085157. n!!!!!! = A085158. n!!!!!!! = A114799. n!!!!!!!! = A114800. n!!!!!!!!! = A114806. Sequence in context: A104413 A127064 A279850 * A215092 A345018 A309079 Adjacent sequences: A117604 A117605 A117606 * A117608 A117609 A117610 KEYWORD nonn AUTHOR Jonathan Vos Post, Apr 06 2006 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified February 24 04:32 EST 2024. Contains 370288 sequences. (Running on oeis4.)