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A141491 Conjectured to be complete list of numbers not of the form 5*x^2 + 3*triangular number + 2*triangular number. 8
1, 4, 13, 19, 27, 46, 73, 97, 111, 123, 151, 168 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..12.

Ben Kane and Zhi-Wei Sun, On almost universal mixed sums of squares and triangular numbers, arXiv:0808.2761

MATHEMATICA

Reap[For[n = 1, n <= 200, n++, If[FindInstance[n == 5x^2 + 3y(y+1)/2 + 2z(z+1)/2, {x, y, z}, Integers] == {}, Print[n]; Sow[n]]]][[2, 1]] (* Jean-Fran├žois Alcover, Oct 01 2018 *)

CROSSREFS

Cf. A141464, A141497.

Cf. A141273, A141386, A141423, A141428, A141443, A141463.

Sequence in context: A191253 A075327 A267767 * A292363 A119048 A319259

Adjacent sequences:  A141488 A141489 A141490 * A141492 A141493 A141494

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Sep 05 2008

STATUS

approved

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Last modified August 21 22:32 EDT 2019. Contains 326169 sequences. (Running on oeis4.)