153401

Appears in sequences

• Strong pseudoprimes to base 13.at n=26A020239
• Strong pseudoprimes to base 50.at n=33A020276
• Strong pseudoprimes to base 97.at n=37A020323
• a(n) = ceiling((9*(9/4)^n - 4) / 5).at n=14A108870
• Number of slanted 2 X n (i=1..2) X (j=i..n+i-1) 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value.at n=25A165394