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A305728 Numbers of the form 216*p^3, where p is a Pythagorean prime (A002144). 1
27000, 474552, 1061208, 5268024, 10941048, 14886936, 32157432, 49027896, 84027672, 152273304, 197137368, 222545016, 279726264, 311665752, 555412248, 714516984, 835896888, 1118386872, 1280824056, 1552836312, 1651400568, 2593941624, 2732256792, 3023464536, 3666512088 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No term can be written as x^2 + y^2 + z^9.

LINKS

Colin Barker, Table of n, a(n) for n = 1..1000

W. Jagy and I. Kaplansky, Sums of Squares, Cubes and Higher Powers, Experimental Mathematics, vol. 4 (1995), p. 171 (see Theorem under Higher powers).

MAPLE

P := select(p -> isprime(p), [seq(n, n=5..1000, 4)]):

seq((6*p)^3, p in P); # Peter Luschny, Jun 22 2018

MATHEMATICA

P = Select[Range[5, 300, 4], PrimeQ];

A305728 = (6P)^3 (* Jean-François Alcover, Jun 22 2018 *)

PROG

(MAGMA) [216*p^3: p in PrimesUpTo(300) | IsOne(p mod 4)];

(PARI) first(n) = my(res=List()); forprime(p=5, oo, if(p%4 == 1, listput(res, (6*p)^3); n--; if(n==0, return(res)))) \\ David A. Corneth, Jun 27 2018

CROSSREFS

Cf. A002144, A016911, A080169.

Sequence in context: A227348 A176359 A162144 * A253485 A253480 A186136

Adjacent sequences:  A305725 A305726 A305727 * A305729 A305730 A305731

KEYWORD

nonn

AUTHOR

Bruno Berselli, Jun 22 2018

STATUS

approved

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Last modified June 25 07:53 EDT 2019. Contains 324347 sequences. (Running on oeis4.)