|
|
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
|
|
|
|