141759
domain: N
Appears in sequences
- a(0)=1, a(n) = sigma_3(2n).at n=25A091986
- a(n) = sigma_3(3n+2).at n=16A092343
- Number of (n+1) X (n+1) 0..2 arrays with the number of clockwise edge increases in 2 X 2 subblocks nondecreasing, and counterclockwise edge increases nonincreasing, rightwards and downwards.at n=2A206534
- Number of (n+1) X 4 0..2 arrays with the number of clockwise edge increases in 2 X 2 subblocks nondecreasing, and counterclockwise edge increases nonincreasing, rightwards and downwards.at n=2A206537
- T(n,k) = number of (n+1) X (k+1) 0..2 arrays with the number of clockwise edge increases in 2 X 2 subblocks nondecreasing, and counterclockwise edge increases nonincreasing, rightwards and downwards.at n=12A206542
- Let sequence B_n={b_m} be defined by: b_1=prime(n), b_2=prime(n+1); for m>=3, b_m=b_(m-2)+b_(m-1) if b_(m-2)+b_(m-1) is not semiprime, otherwise b_m is the least prime divisor of b_(m-2)+b_(m-1). Then a(n) is the maximal term of sequence B_n, or a(n)=0 if B_n is unbounded.at n=71A221218