19267

Properties

Appears in sequences

• Convolution of natural numbers >= 3 and (Fib(2), Fib(3), Fib(4), ...).at n=15A023554
• a(n) = Sum_{i=0..floor(n/2)} T(2i,n-2i), array T as in A049723.at n=32A049726
• Discriminants of imaginary quadratic fields with class number 25 (negated).at n=31A056987
• Class 6+ primes.at n=22A081634
• Primes p such that the sum of the digits of p is not prime, but the sum of the cubes of the digits of p is prime.at n=31A091365
• Recurrence sequence based on positions of digits in decimal places of phi, the Golden Ratio = (1+sqrt(5))/2.at n=15A098324
• Primes with subscripts described in A098213.at n=7A099640
• Primes congruent to 28 mod 53.at n=38A142558
• Primes congruent to 33 mod 59.at n=39A142760
• Primes congruent to 52 mod 61.at n=37A142850
• Primes in toothpick sequence A153003.at n=35A153005
• Primes p such that p^2 - 2 is a 5-almost prime.at n=30A156620
• Primes p such that 5*p+2, 7*p+4 and 11*p+6 are also prime.at n=21A173880
• Primes remaining primes under map 2<=>9 (interchange of decimal digits 2 and 9).at n=36A198146
• Number of zero-sum nX1 -1..1 arrays with every element equal to at least one horizontal or vertical neighbor.at n=18A201840
• Primes of the form (n^2+2)/6 where n^2+1 is prime.at n=13A215429
• Number of cusps in a class of degree-3n complex algebraic surfaces.at n=14A225018
• Primes whose base-7 representation also is the base-4 representation of a prime.at n=50A235617
• Triangle T(n,k) read by rows: T(n,k) is the number of compositions of n with k parts p at position p (fixed points), n>=0, 0<=k<=A003056(n).at n=67A238350
• Number of compositions p(1)+p(2)+...+p(k) = n such that for no part p(i) = i (compositions without fixed points).at n=17A238351