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A264798
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Irregular triangle read by rows: odd-valued terms of A094728(n+1).
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1
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1, 3, 9, 5, 15, 7, 25, 21, 9, 35, 27, 11, 49, 45, 33, 13, 63, 55, 39, 15, 81, 77, 65, 45, 17, 99, 91, 75, 51, 19, 121, 117, 105, 85, 57, 21, 143, 135, 119, 95, 63, 23, 169, 165, 153, 133, 105, 69, 25, 195, 187, 171, 147, 115, 75, 27, 225, 221, 209, 189, 161, 125, 81, 29, 255, 247
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OFFSET
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0,2
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COMMENTS
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A094728(n+1) comes from A120070(n+2). a(n) approximates frequencies of the spectral lines of the hydrogen atom.
Row sums: 1, 3, 14, 22, ... = A024598(n+1).
Row sums of A261046(n) = 1, 3, 8, 12, ... = A014255(n). See the formula.
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LINKS
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FORMULA
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EXAMPLE
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Irregular triangle begins:
1,
3,
9, 5,
15, 7,
25, 21, 9,
35, 27, 11,
49, 45, 33, 13,
63, 55, 39, 15,
...
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MATHEMATICA
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Table[n^2 - k^2, {n, 14}, {k, 0, n - 1}] /. n_ /; EvenQ@ n -> Nothing // Flatten (* Michael De Vlieger, Nov 25 2015 *)
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PROG
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(PARI) for(n=1, 20, for(k=0, n-1, s=n^2-k^2; if(s%2, print1(s, ", ")))) \\ Derek Orr, Dec 24 2015
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CROSSREFS
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KEYWORD
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nonn,easy,tabf
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AUTHOR
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STATUS
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approved
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