23687

Properties

Appears in sequences

• Primes of the form 6n^2 - 2n - 1.at n=21A099007
• A McMullen transform involving x->x+1/x of Lehmer's polynomial gives the polynomial used to get this expansion sequence: p(x)=1 + x + 10 x^2 + 8 x^3 + 44 x^4 + 28 x^5 + 113 x^6 + 57 x^7 + 191 x^8 + 79 x^9 + 227 x^10 + 79 x^11 + 191 x^12 + 57 x^13 + 113 x^14 + 28 x^15 + 44 x^16 + 8 x^17 + 10 x^18 + x^19 + x^20.at n=19A143465
• Primes congruent to 35 mod 73.at n=33A154628
• Primes p such that 2*p^4-+21 are also prime.at n=34A174367
• Number of 3 X n arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and columns, 0..1 3 X n array.at n=27A219520
• Number of third differences of arrays of length 5 of numbers in 0..n.at n=25A228261
• Quadruple Hex-primes: let f(n) = A102489(n); then sequence lists primes p such that f(p), f(f(p)). f(f(f(p))) and f(f(f(f(p)))) are also primes.at n=18A237440
• Initial members of prime quadruples (n, n+2, n+144, n+146).at n=18A248523
• Initial members of prime quadruples (n, n+2, n+54, n+56).at n=25A248661
• G.f.: Sum_{n>=0} x^n * (x^n + i)^n / (1 + i*x^(n+1))^(n+1), where i^2 = -1.at n=90A323675
• Odd coefficients in Sum_{n>=0} x^n * (x^n + i)^n / (1 + i*x^(n+1))^(n+1), where i^2 = -1.at n=9A323676
• Primes in Pi (variant of A336520): a(n) is the smallest prime factor of A090897(n) that does not appear in earlier terms of a, or 1, if no such factor exists.at n=30A336519
• Primes in Pi: a(n) is the smallest prime factor of A090897(n) that does not appear in earlier terms of A090897, or 1, if no such factor exists.at n=30A336520
• Position of the first occurrence of n in A337474.at n=35A337476
• Primes p such that p+2, (p^2-1)/2+p and (p^2+3)/2+3*p are also prime.at n=8A352948
• Lesser of twin primes p such that p and p+2 are both in A115591.at n=22A367318
• Prime numbersat n=2636