A360841 4-full numbers (A036967) sandwiched between twin primes.
2592, 139968, 995328, 37340352, 63700992, 99574272, 169869312, 414720000, 1399680000, 4076863488, 10871635968, 17714700000, 22781250000, 25312500000, 35888419872, 51840000000, 82012500000, 98802571392, 135304020000, 136136700000, 170749797552, 174960000000, 196730062848
Offset: 1
Keywords
Examples
2592 = 2^5 * 3^4 is a term since it is 4-full and 2591 and 2593 are twin primes.
Links
- Amiram Eldar, Table of n, a(n) for n = 1..1520 (terms below 3*10^19)
- Eric Weisstein's World of Mathematics, Twin Primes.
- Wikipedia, Powerful number: Generalization.
- Index entries for sequences related to powerful numbers.
Programs
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Mathematica
Select[6*Range[2*10^5], PrimeQ[# - 1] && PrimeQ[# + 1] && Min[FactorInteger[#][[;; , 2]]] > 3 &]
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PARI
is(n) = isprime(n-1) && isprime(n+1) && vecmin(factor(n)[,2]) > 3;