30277632

Appears in sequences

• Triangle T, read by rows, where matrix power T^4 has powers of 4 in the secondary diagonal: [T^4](n+1,n) = 4^(n+1), with all 1's in the main diagonal and zeros elsewhere.at n=15A117254
• Column 0 of triangle A117254.at n=5A117255
• Triangle T, read by rows, where matrix power T^-2 has -2^(n+1) in the secondary diagonal: [T^-2](n+1,n) = -2^(n+1), with all 1's in the main diagonal and zeros elsewhere.at n=29A117265
• a(n) is the least number with n prime factors (counted with multiplicity) that is the concatenation of two primes.at n=19A374669