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A139546 Numbers of form x^2+5y^2 (x>=0,y>=0) with repetition. 0
0, 1, 4, 5, 6, 9, 9, 14, 16, 20, 21, 21, 24, 25, 29, 30, 36, 36, 41, 45, 45, 46, 49, 49, 54, 54, 56, 61, 64, 69, 69, 70, 80, 81, 81, 81, 84, 84, 86, 89, 94, 96, 100, 101, 105, 105, 109, 116, 120, 121, 125, 126, 126, 126, 129, 129, 134, 141, 141, 144, 144, 145, 149, 150 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Primes in the sequence occur only once.

REFERENCES

David A. Cox, "Primes of the Form x^2 + n y^2", Wiley, 1989.

LINKS

Table of n, a(n) for n=1..64.

EXAMPLE

0 = 0^2+5*0^2,

9 = 2^2+5*1^2 = 3^2+5*0^2,

81 = 1^2+5*4^2 = 6^2+5*3^2 = 9^2+5*0^2,

441: {x,y}={6,9},{11,8},{14,7},{19,4},{21,0}.

CROSSREFS

Cf. A033205.

Sequence in context: A195355 A049466 A196551 * A029776 A064931 A177103

Adjacent sequences:  A139543 A139544 A139545 * A139547 A139548 A139549

KEYWORD

nonn

AUTHOR

Zak Seidov, Apr 26 2008

STATUS

approved

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Last modified May 25 04:50 EDT 2019. Contains 323539 sequences. (Running on oeis4.)