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A069354
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Lowest base with simple divisibility test for n primes; smallest B such that omega(B)+omega(B-1)=n.
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0
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2, 3, 6, 15, 66, 210, 715, 7315, 38571, 254541, 728365, 11243155, 58524466
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Described on Munafo's web page under the entry for the number 66
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LINKS
| Robert Munafo, Notable Properties of Specific Numbers
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EXAMPLE
| a(4)=15 because in base 15 you can test for divisibility by 4 different primes (3 and 5 directly, 2 and 7 by "casting out 14's")
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MAPLE
| A069354_list := proc(n) local i, L, Max;
Max := 1; L := NULL;
for i from 2 to n do
if nops(numtheory[factorset](i*(i-1))) = Max
then Max := Max + 1; L := L, i fi;
od;
L end:
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CROSSREFS
| Cf. A001221.
Sequence in context: A061059 A059842 A001529 * A116632 A007364 A014627
Adjacent sequences: A069351 A069352 A069353 * A069355 A069356 A069357
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KEYWORD
| nonn
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AUTHOR
| Robert P. Munafo (mrob(AT)mrob.com), Nov 19 2002
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