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A123064 Numbers represented by the quadratic form 2 x^2 + xy + 4 y^2. 7
0, 2, 4, 5, 7, 8, 10, 14, 16, 18, 19, 20, 25, 28, 32, 35, 36, 38, 40, 41, 45, 49, 50, 56, 59, 62, 63, 64, 70, 71, 72, 76, 80, 82, 90, 94, 95, 97, 98, 100, 101, 103, 107, 109, 112, 113, 118, 124, 125, 126, 128, 133, 134, 140, 142, 144, 152, 155, 157, 160, 162, 163, 164, 171, 175 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

J. H. Conway, The Sensual (Quadratic) Form, M.A.A., 1997, p. 82.

LINKS

Table of n, a(n) for n=1..65.

N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)

PROG

(MAGMA) L:=LatticeWithGram(2, [4, 1, 1, 8] ); T<q> := ThetaSeries(L, 500); T;

CROSSREFS

Cf. A123063, A123065, A123067, A123068.

Primes: A106872.

Sequence in context: A231979 A072013 A326669 * A108513 A029749 A018519

Adjacent sequences:  A123061 A123062 A123063 * A123065 A123066 A123067

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Sep 27 2006

STATUS

approved

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Last modified July 23 16:03 EDT 2021. Contains 346259 sequences. (Running on oeis4.)