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A127601 Integer part of 4th root of product of first n primes. 5
1, 1, 1, 2, 3, 6, 13, 26, 55, 122, 283, 669, 1650, 4176, 10694, 28002, 75555, 209402, 585212, 1674296, 4860120, 14206194, 42353033, 127836257, 392646335, 1232237672, 3906383039, 12444691408, 40024883480, 129326254765 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,4
COMMENTS
For n>=6, a(n) >= prime(n+1).
a(n) gives the number of pairs within A002110(n) of the form {x, x^4} where x is nonzero positive integer. - Soumyadeep Dhar, May 16 2021
LINKS
MATHEMATICA
a = {}; Do[b = 1; Do[b = b Prime[x], {x, 1, n}]; AppendTo[a, Floor[b^(1/4)]], {n, 1, 50}]; a
PROG
(PARI) a(n)={sqrtnint(vecprod(primes(n)), 4)} \\ Andrew Howroyd, Apr 27 2021
CROSSREFS
Sequence in context: A293315 A052702 A058766 * A030038 A030040 A274493
KEYWORD
nonn
AUTHOR
Artur Jasinski, Jan 19 2007
EXTENSIONS
a(0)=1 prepended by Soumyadeep Dhar, Apr 28 2021
STATUS
approved

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Last modified February 21 10:12 EST 2024. Contains 370228 sequences. (Running on oeis4.)