296341

Appears in sequences

• Hyperperfect numbers: k = m*(sigma(k) - k - 1) + 1 for some m > 1.at n=23A007592
• Hyperperfect numbers: x such that x = 1 + k*(sigma(x)-x-1) for some k > 0.at n=27A034897
• p(p^2-p+1) as p runs through the primes.at n=18A083558
• Square array T(n, k) = Product_{j=1..n} ( Sum_{i=0..j-1} ( (k+1)^7 - Sum_{m=1..5} (k+1)^m )^i ) with T(n, 0) = n!, read by antidiagonals.at n=13A156888
• Semiprimes pq with pq - 1 divisible by p + q.at n=15A164643
• Semiprimes of the form p*(p^2 - p + 1).at n=4A190275
• Unitary hyperperfect numbers.at n=29A225150
• Number of (n+1)X(1+1) 0..2 arrays with the upper median plus the lower median minus the minimum of every 2X2 subblock equal.at n=7A236782
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the upper median plus the lower median minus the minimum of every 2X2 subblock equal.at n=28A236789
• Bi-unitary k-hyperperfect numbers: numbers m such that m = 1 + k * (bsigma(m) - m - 1) where bsigma(m) is the sum of bi-unitary divisors of m (A188999) and k >= 1 is an integer.at n=22A309568