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A054686
Multiset consisting of squares and triangular numbers.
5
0, 0, 1, 1, 3, 4, 6, 9, 10, 15, 16, 21, 25, 28, 36, 36, 45, 49, 55, 64, 66, 78, 81, 91, 100, 105, 120, 121, 136, 144, 153, 169, 171, 190, 196, 210, 225, 231, 253, 256, 276, 289, 300, 324, 325, 351, 361, 378, 400, 406, 435, 441, 465, 484, 496, 528
OFFSET
1,5
COMMENTS
Terms of A001110 occur twice. [Reinhard Zumkeller, Aug 03 2011]
REFERENCES
Hofstadter, D. R., Fluid Concepts and Creative Analogies: Computer Models of the Fundamental Mechanisms of Thought, (together with the Fluid Analogies Research Group), NY: Basic Books, 1995. p. 15.
LINKS
MATHEMATICA
stnos[max_]:=Module[{sqmax=Floor[Sqrt[max]], trmax=Floor[(Sqrt[ 8max+1]- 1)/2]}, Sort[Join[Range[0, sqmax]^2, Accumulate[Range[0, trmax]]]]]; stnos[ 528] (* Harvey P. Dale, Feb 06 2012 *)
PROG
(Haskell)
a054686_list = merge a000290_list a000217_list where
merge xs'@(x:xs) ys'@(y:ys)
| x <= y = x : merge xs ys'
| otherwise = y : merge xs' ys
-- Reinhard Zumkeller, Aug 03 2011
(PARI) upTo(lim)=vecsort(concat(vector(sqrtint(lim\1)+1, n, (n-1)^2), vector(floor(sqrt(2+2*lim)+1/2), n, n*(n-1)/2))) \\ Charles R Greathouse IV, Aug 04 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Michael Somos, Apr 19 2000
EXTENSIONS
Offset fixed by Reinhard Zumkeller, Aug 04 2011
STATUS
approved