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A354217
Primes p such that the squarefree kernel of the product of the composite numbers between p and the next prime after p (A076978) sets a new record.
4
3, 5, 7, 13, 19, 23, 31, 47, 53, 73, 83, 89, 113, 199, 211, 293, 467, 523, 887, 1129, 1327, 2971, 3271, 4297, 4831, 5591, 8467, 9551, 12853, 14107, 15683, 19609, 25471, 31397, 89689, 107377, 134513, 155921, 265621, 338033, 360653, 370261, 492113, 1098847, 1349533
OFFSET
1,1
MATHEMATICA
s = Array[Times @@ FactorInteger[Times @@ Range[#1 + 1, #2 - 1]][[All, 1]] & @@ Map[Prime, # + {0, 1}] &, 2^15]; Prime@ Map[FirstPosition[s, #][[1]] &, Union@ FoldList[Max, s]] (* Michael De Vlieger, May 20 2022 *)
PROG
(PARI) a354217(limit) = {my(mp=0, pp=3); forprime(p=5, limit, my(L=List()); for(j=pp+1, p-1, my(f=factor(j), nf=#f~); for(k=1, nf, listput(~L, f~[1, k]))); listsort(L, 1); my(mpp=prod(k=1, #L, L[k])); if(mpp>mp, print1(pp, ", "); mp=mpp); pp=p)};
a354217(1500000)
CROSSREFS
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, May 19 2022
STATUS
approved