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A024967 Positions of primes in A003072. 1
1, 3, 5, 7, 11, 17, 25, 28, 34, 38, 39, 41, 46, 48, 53, 57, 68, 72, 73, 77, 80, 91, 100, 108, 110, 113, 115, 116, 120, 123, 128, 135, 144, 156, 161, 175, 185, 189, 198, 202, 205, 217, 224, 231, 235, 245, 247, 252, 255, 267, 273, 275, 276, 278, 285, 297, 301, 304, 315, 320, 324 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert Israel, Table of n, a(n) for n = 1..8446

MAPLE

N:= 10000: # for members of A003072 up to N

S:= {}:

for x from 1 while 3*x^3 <= N do

  for y from x while x^3+2*y^3<=N do

    for z from y do

      v:= x^3+y^3+z^3;

      if v > N then break fi;

      S:= S union {v}

od od od:

S:= sort(convert(S, list)):

select(i -> isprime(S[i]), [$1..nops(S)]); # Robert Israel, Aug 27 2019

CROSSREFS

Sequence in context: A065557 A266164 A152999 * A135246 A109543 A229168

Adjacent sequences:  A024964 A024965 A024966 * A024968 A024969 A024970

KEYWORD

nonn

AUTHOR

Clark Kimberling

EXTENSIONS

More terms from Sean A. Irvine, Jul 30 2019

STATUS

approved

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Last modified October 17 16:51 EDT 2019. Contains 328120 sequences. (Running on oeis4.)