A360840 3-full numbers (A036966) sandwiched between twin primes.

432, 2592, 139968, 444528, 472392, 995328, 3456000, 5174928, 6561000, 10125000, 15552000, 15804072, 17496000, 25299648, 28449792, 37340352, 54675000, 63700992, 85957848, 88723728, 99574272, 120891312, 144027072, 169869312, 177147000, 197413632, 253125000, 259308000

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Twin Primes.

Wikipedia, Powerful number: Generalization.

Index entries for sequences related to powerful numbers.

Example

432 = 2^4 * 3^3 is a term since it is 3-full and 431 and 433 are twin primes.

Mathematica

Select[6*Range[10^6], PrimeQ[# - 1] && PrimeQ[# + 1] && Min[FactorInteger[#][[;; , 2]]] > 2 &]

Prog

(PARI) is(n) = isprime(n-1) && isprime(n+1) && vecmin(factor(n)[, 2]) > 2;

Crossrefs

Intersection of A014574 and A036966.

Subsequence of A113839.

Sequence in context: A250815 A006910 A015229 * A248460 A234327 A174717

Adjacent sequences: A360837 A360838 A360839 * A360841 A360842 A360843

Keyword

nonn

Author

Amiram Eldar, Feb 23 2023

Status

approved