A360842
5-full numbers (A069492) sandwiched between twin primes.
Original entry on oeis.org
139968, 995328, 63700992, 4076863488, 17714700000, 82012500000, 98802571392, 174960000000, 445240556352, 641194278912, 889223142528, 1059917571072, 1594323000000, 1663012435968, 2348273369088, 3333709317312, 5717741400000, 16260080320512, 19144761127488, 28697814000000
Offset: 1
139968 = 2^6 * 3^7 is a term since it is 5-full and 139967 and 139969 are twin primes.
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Select[6*Range[2*10^5], PrimeQ[# - 1] && PrimeQ[# + 1] && Min[FactorInteger[#][[;; , 2]]] > 4 &]
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is(n) = isprime(n-1) && isprime(n+1) && vecmin(factor(n)[,2]) > 4;
A360843
6-full numbers (A069493) sandwiched between twin primes.
Original entry on oeis.org
139968, 98802571392, 174960000000, 889223142528, 1594323000000, 2348273369088, 19144761127488, 28697814000000, 56358560858112, 84537841287168, 150289495621632, 186624000000000, 328341017826432, 369056250000000, 392147405854848, 578415690713088, 597871125000000
Offset: 1
139968 = 2^6 * 3^7 is a term since it is 6-full and 139967 and 139969 are twin primes.
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Select[6*Range[10^5], PrimeQ[# - 1] && PrimeQ[# + 1] && Min[FactorInteger[#][[;; , 2]]] > 5 &]
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is(n) = isprime(n-1) && isprime(n+1) && vecmin(factor(n)[,2]) > 5;
A360844
a(n) is the least k-full number that is sandwiched between twin primes.
Original entry on oeis.org
4, 432, 2592, 139968, 139968, 174960000000, 56358560858112, 84537841287168, 578415690713088, 578415690713088, 1141260857376768, 61628086298345472, 61628086298345472, 61628086298345472, 322850407500000000000000000000, 322850407500000000000000000000, 62518864539857068333550694039552
Offset: 2
The first 3 terms, their factorizations and the corresponding twin primes are:
n | a(n) prime factorization A051904(a(n)) {a(n)-1, a(n)+1}
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2 | 4 2^2 2 {3, 5}
3 | 432 2^4 * 3^3 3 {431, 433}
4 | 2592 2^5 * 3^4 4 {2591, 2593}
Showing 1-3 of 3 results.
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