252500

Appears in sequences

• Starting index of a string of 6 or more consecutive equal digits in decimal expansion of Pi.at n=4A049534
• Starting positions of strings of four 6's in the decimal expansion of Pi.at n=29A083626
• Starting positions of strings of five 6's in the decimal expansion of Pi.at n=5A083627
• a(n)=5*a(n-1)+30*a(n-2) for n>=3, a(0)=1, a(1)=5, a(2)=50 .at n=6A133646
• Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1001-1111-1001 pattern in any orientation.at n=20A146931
• a(n) = Sum_{k=0..floor(n/4)} (5*k+1) * binomial(3*n-7*k+1,n-4*k)/(3*n-7*k+1).at n=9A390486