26887

Appears in sequences

• a(n) = (8*n+1)*(8*n+7).at n=20A001533
• Every suffix prime and no 0 digits in base 9 (written in base 9).at n=49A024784
• Numbers k such that 111*2^k-1 is prime.at n=42A050581
• Odd composites (including 1 in the count) where the number 3 mod 4 equals the number 1 mod 4.at n=8A093181
• a(n) = RMS( A141393(0) through A141393(n) ).at n=19A141394
• Composite squarefree numbers n such that p(i)-5 divides n+5, where p(i) are the prime factors of n.at n=15A225705
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 203", based on the 5-celled von Neumann neighborhood.at n=34A270727