This site is supported by donations to The OEIS Foundation. Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A140250 a(n) is the largest cube <= A066525(n). 3
 343, 15625, 34965783, 106496424, 3023464536, 3659383421, 7222633237, 10403062487, 11179320256, 11993263569, 25881801912, 36495256013, 40672093519, 47516597848, 49917330568, 63616767488, 84200449887, 96323848704, 573234910443, 972947676429 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Suggested by Carlos Rivera's Prime Puzzles & Problems Connection, Puzzle 443 (which asks if a sum of consecutive cubes can be a cube or a prime cube). LINKS Nathaniel Johnston, Table of n, a(n) for n = 1..1000 Carlos Rivera, Puzzle 443. Sum of cubes of consecutive primes, The Prime Puzzles and Problems Connection. EXAMPLE In A066525 the first term is 503, the sum of cubes of the first four consecutive primes, 2 3 5 7. The cube just less than 503 is 343, a(1) in this sequence. MAPLE with(numtheory): P:=proc(n) add(ithprime(k)^3, k=1..n): end: A098563 := proc(n)local m: option remember: if(n=0)then return 0: fi: m:=procname(n-1)+2: while true do if(isprime(P(m)))then return m:fi: m:=m+2:od: end: A140250 := proc(n)return floor(surd(P(A098563(n)), 3))^3: end: seq(A140250(n), n=1..20); # Nathaniel Johnston, Apr 21 2011 CROSSREFS Cf. A066525, A098563, A140251. Sequence in context: A224427 A134263 A270820 * A117197 A269554 A046236 Adjacent sequences:  A140247 A140248 A140249 * A140251 A140252 A140253 KEYWORD nonn AUTHOR Enoch Haga, May 15 2008 EXTENSIONS Edited by N. J. A. Sloane, Aug 25 2008 a(11)-a(20) from Nathaniel Johnston, Apr 21 2011 STATUS approved

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

Last modified August 18 04:50 EDT 2019. Contains 326072 sequences. (Running on oeis4.)