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A083002
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Smallest oblong number having at least n distinct prime divisors.
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4
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2, 6, 30, 210, 4290, 43890, 510510, 53501910, 1487683470, 64790866140, 530514844860, 126408523110870, 3425113062060690, 660393717163700520, 26657280574571657010, 3448055881024876471350, 308480161111936386482910
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OFFSET
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1,1
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COMMENTS
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Oblong numbers are those of the form n(n+1) = A002378(n) = 2*A000217(n).
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LINKS
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EXAMPLE
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a(4)= 210 = 2*3*5*7.
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PROG
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(PARI) {odf(m) = print1(0", "); for(n=1, m, k=1; while(omega(k*(k+1))!=n, k++); print1(k*(k+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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EXTENSIONS
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STATUS
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approved
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