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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

Table of n, a(n) for n=1..44.

EXAMPLE

25 is in the sequence because A001694(6)=25, A001694(7)=27, without primes between them.

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 July 25 04:48 EDT 2017. Contains 289779 sequences.