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A073818 a(n) = max(prime(i)*(n+1-i) | 1 <= i <= n). 5
2, 4, 6, 10, 15, 22, 33, 44, 55, 68, 85, 102, 119, 145, 174, 203, 232, 261, 296, 333, 370, 410, 451, 492, 533, 590, 649, 708, 767, 826, 885, 944, 1005, 1072, 1139, 1207, 1278, 1358, 1455, 1552, 1649, 1746, 1843, 1940, 2037, 2134, 2231, 2328, 2425, 2540, 2667 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Smallest m such that m! is divisible by product_{k=0..n} A002110(k).

LINKS

Table of n, a(n) for n=1..51.

EXAMPLE

For n = 5, we take the first 5 primes in ascending order and multiply them by the numbers from 5 to 1 in descending order: 2*5 = 10 3*4 = 12 5*3 = 15 7*2 = 14 11*1 = 11. The largest product is 15, so a(5) = 15.

PROG

(PARI) a(n) = {ret = 0; for (i=1, n, ret = max (ret, prime(i)*(n+1-i)); ); return (ret); } \\ Michel Marcus, Jun 16 2013

CROSSREFS

Cf. A073819, A073820.

Sequence in context: A073470 A086182 A035294 * A342091 A239288 A306145

Adjacent sequences:  A073815 A073816 A073817 * A073819 A073820 A073821

KEYWORD

easy,nonn

AUTHOR

David Wasserman, Aug 13 2002

EXTENSIONS

Thanks to Naohiro Nomoto for correcting an editing error, Jun 01 2003

STATUS

approved

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Last modified April 22 14:18 EDT 2021. Contains 343177 sequences. (Running on oeis4.)