47491

Properties

Appears in sequences

• a(n) = T(2*n+1, n), array T as in A047080.at n=10A047086
• Primes p such that the differences between the 5 consecutive primes starting with p are (6,4,6,6).at n=11A078964
• Prime numbers p such that p +- ((p-1)/5) are primes.at n=32A137714
• Primes p such that 42*p-1, 42*p+1 and 48*p-1, 48*p+1 are twin primes.at n=14A138697
• Numbers p of primitive Pythagorean triangles such that perimeters and products of 3 sides are Averages of twin prime pairs, q=p+1, a=q^2-p^2, c=q^2+p^2, b=2*p*q, ar=a*b/2; s=a+b+c, s-+1 are primes, pr=a*b*c, pr-+1 are primes.at n=4A155178
• Number of permutations that avoid the barred pattern bar{1}43bar{5}2.at n=10A201497
• Number of symmetric bargraphs having semiperimeter n (n>=2).at n=19A273905
• Number of nX3 0..1 arrays with every element equal to 1, 2, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=7A303406
• T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=52A303410
• Greatest prime dividing 2^n + n.at n=32A359685
• Prime numbersat n=4894