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A137532
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a(n) is the smallest positive integer k such that d(k) = d(k+n) = 2*n, where d(m) (A000005) is the number of positive divisors of m, or 0 if no such k exists.
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1
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2, 6, 172, 66, 15952, 84, 22592, 888, 2196, 3750, 459932661, 660, 86817796083, 185152, 143366096, 5304, 17685013528576, 3150, 1786574475624429, 1272510, 29059703104, 12872682, 4817557477673402368, 9576, 85608255863, 15744471040, 1179648, 124718750, 1765038427619364800823267
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OFFSET
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1,1
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LINKS
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PROG
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(PARI) lq080419b(n, a)=n*=2; until(0, numdiv(a++)==n || next; numdiv(a+n\2)==n && break); a
for(i=1, 99, print1(lq080419b(i)", "))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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