25969

Properties

Appears in sequences

• Crystal ball sequence for hexagonal close-packing.at n=19A007202
• Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 98 ones.at n=30A031866
• Primes whose consecutive digits differ by 3 or 4.at n=40A048415
• Start with a(1)=1; for n >= 1, a(n+1)=a(n)+a(k) with k=[n - n-th digit of sqrt(2)]. If k<0 or k=0, then a(k)=0.at n=36A133393
• Primes p such that q*p+-Mod(p,q) are primes, for q=7.at n=35A178387
• Number of (w,x,y,z) with all terms in {0,...,n} and max{w,x,y,z}>=2*min{w,x,y,z}.at n=12A212741
• Primes p such that 2p^2-1, 3p^2-2 and 4p^2-3 are also prime.at n=11A213079
• Number of 3 X 3 0..n symmetric arrays with all rows summing to floor(n*3/2).at n=37A213801
• Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 4.at n=9A245749
• Integers k such that (13*2^k)^8 + 1 is prime.at n=16A319217
• Prime numbers congruent to 49 or 121 modulo 240 representable by x^2 + 960*y^2.at n=38A325090
• Sum_{n>=0} a(n) * x^n / (n!)^2 = exp(1 + x - BesselI(0,2*sqrt(x))).at n=8A337166
• Expansion of (1/x) * Series_Reversion( x * (1-x) / B(x) ), where B(x) is the g.f. of A001764.at n=6A381911
• Primes having only {2, 5, 6, 9} as digits.at n=33A386161
• Prime numbersat n=2857