A118750
a(n) = product[k=1..n] P(k), where P(k) is the largest prime <= 3*k. a(n) = product[k=1..n] A118749(k).
Original entry on oeis.org
3, 15, 105, 1155, 15015, 255255, 4849845, 111546435, 2565568005, 74401472145, 2306445636495, 71499814731345, 2645493145059765, 108465218947450365, 4664004414740365695, 219208207492797187665, 10302785752161467820255
Offset: 1
A118455
a(1)=1, a(n) = Product_{k=2..n} P(k), where P(k) is the largest prime <= k.
Original entry on oeis.org
1, 2, 6, 18, 90, 450, 3150, 22050, 154350, 1080450, 11884950, 130734450, 1699547850, 22094122050, 287223586650, 3733906626450, 63476412649650, 1079099015044050, 20502881285836950, 389554744430902050
Offset: 1
a(6)=450 because the largest primes that do not exceed 2,3,4,5 and 6 are, respectively 2,3,3,5 and 5, having product 2*3*3*5*5=450.
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a:=proc(n) if n=1 then 1 else product(prevprime(k+1),k=2..n) fi end: seq(a(n),n=1..23); # Emeric Deutsch, Apr 30 2006
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FoldList[Times, 1, Table[Prime@ PrimePi@ k, {k, 2, 20}]] (* Michael De Vlieger, Aug 21 2017 *)
A118747
a(n) = product[k=1..n] P(k), where P(k) is the largest prime <= 2*k. a(n) = product[k=1..n] A060308(k).
Original entry on oeis.org
2, 6, 30, 210, 1470, 16170, 210210, 2732730, 46456410, 882671790, 16770764010, 385727572230, 8871734161290, 204049885709670, 5917446685580430, 183440847252993330, 5686666264842793230, 176286654210126590130
Offset: 1
A118752
a(n) = product[k=0..n] P(k), where P(k) is the smallest prime > 3*n. a(n) = product[k=0..n] A118751(k).
Original entry on oeis.org
2, 10, 70, 770, 10010, 170170, 3233230, 74364290, 2156564410, 62540367890, 1938751404590, 71733801969830, 2654150672883710, 108820177588232110, 4679267636293980730, 219925578905817094310, 11656055682008305998430
Offset: 0
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Rest[FoldList[Times,1,Table[NextPrime[3n],{n,0,20}]]] (* Harvey P. Dale, Mar 09 2014 *)
A118748
a(n) = Product_{k=1..n} P(k), where P(k) is the smallest prime >= 2*k.
Original entry on oeis.org
2, 10, 70, 770, 8470, 110110, 1871870, 31821790, 604614010, 13906122230, 319840811290, 9275383527410, 268986122294890, 7800597546551810, 241818523943106110, 8947285385894926070, 331049559278112264590
Offset: 1
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