83340

Appears in sequences

• G.f.: (x+4*x^3+x^5)/((1-x)^2*(1-x^2)^2*(1-x^3)^2).at n=33A083708
• a(n) is a non-palindromic composite located between twin primes whose reverse, which is less than it, is also located between twin primes.at n=34A103741
• Sequence of the "Natural Jewels": a natural jewel is a number that is totally enclosed by prime numbers in a version of Ulam Spiral.at n=31A172294
• Number of 3X3 0..n arrays with each 2X2 subblock determinant nonzero and the array of 2X2 subblock determinants symmetric under 90 degree rotation.at n=13A187529
• Numbers on the square spiral board that are enclosed by four primes.at n=30A341542