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A055039
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Numbers of the form 2^(2i+1)*(8j+7).
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8
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14, 30, 46, 56, 62, 78, 94, 110, 120, 126, 142, 158, 174, 184, 190, 206, 222, 224, 238, 248, 254, 270, 286, 302, 312, 318, 334, 350, 366, 376, 382, 398, 414, 430, 440, 446, 462, 478, 480, 494, 504, 510, 526, 542, 558, 568, 574, 590, 606, 622
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OFFSET
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1,1
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COMMENTS
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The numbers not of the form x^2+y^2+2z^2.
These are the numbers not occurring as norms in the face-centered cubic lattice (cf. A004015).
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LINKS
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FORMULA
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Consists of numbers of the form 6x^2 + 8x^2*(2y -1). (Steve Waterman).
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EXAMPLE
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In base 4: 32, 132, 232, 320, 332, 1032, 1132, 1232, 1320, 1332, 2032,...
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PROG
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(Python)
from itertools import count, islice
def A055039_gen(startvalue=1): # generator of terms >= startvalue
return filter(lambda n:(m:=(~n&n-1).bit_length())&1 and (n>>m)&7==7, count(max(startvalue, 1)))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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