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 A240591 The smaller of a pair of successive powerful numbers (A001694) without any prime number between them. 1
 8, 25, 32, 121, 288, 675, 1331, 1369, 1936, 2187, 2700, 3125, 5324, 6724, 9800, 10800, 12167, 15125, 32761, 39200, 48668, 70225, 79507, 88200, 97336, 107648, 143641, 156800, 212521, 228484, 235224, 280900, 312481, 332928, 456968, 465124, 574564, 674028, 744769, 829921, 830297, 857476, 877952, 940896 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Supersequence of A060355. LINKS EXAMPLE 25 is in the sequence because A001694(6)=25, A001694(7)=27, without primes between them. MATHEMATICA Select[Partition[Join[{1}, Select[Range[10^6], Min@FactorInteger[#][[All, 2]]> 1&]], 2, 1], PrimePi[#[[1]]]==PrimePi[#[[2]]]&][[All, 1]] (* Harvey P. Dale, Mar 28 2018 *) PROG (PARI) ispowerful(n)={local(h); if(n==1, h=1, h=(vecmin(factor(n)[, 2])>1)); return(h)} nextpowerful(n)={local(k); k=n+1; while(!ispowerful(k), k+=1); return(k)} {for(i=1, 10^6, if(ispowerful(i), if(nextprime(i)>=nextpowerful(i), print1(i, ", "))))} CROSSREFS Cf. A001694, A060355, A240590. Sequence in context: A081504 A030796 A266927 * A116086 A270739 A239582 Adjacent sequences:  A240588 A240589 A240590 * A240592 A240593 A240594 KEYWORD nonn AUTHOR Antonio Roldán, Apr 08 2014 STATUS approved

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Last modified December 11 13:25 EST 2018. Contains 318049 sequences. (Running on oeis4.)