229503

Appears in sequences

• Number of n X n 0..14 matrices with all row and column sums equal.at n=3A067222
• Nonprime numbers n such that phi(n) divides n^2 - 1, where phi(n) (A000010) is Euler's totient function.at n=32A098271
• Pseudoquadprimes: p+4 for primes p where p+4 divides p^(p+4) + 4 and p+4 is composite.at n=21A100875
• Concatenation of triangular number k and its 10's complement is prime.at n=35A108970
• Number of 3 X 3 0..n arrays with row and column sums equal.at n=13A202785
• Triangular numbers representable as x*y+x+y such that x and y are triangular numbers, x>=y>0.at n=35A259745
• Triangular numbers representable as x*y+x+y such that x and y are triangular numbers, x>=y>1.at n=29A259746