25217

Appears in sequences

• a(0) = 1, a(n) = 15*n^2 + 2 for n>0.at n=41A010005
• a(n) = T(n,n+3), T given by A027023.at n=12A027025
• Composite numbers such that all divisors >1 have the same number of 1's in binary representation.at n=41A089042
• a(n) = prime(n)*prime(n+3).at n=35A090090
• Equal count of primes congruent to 1 mod 4 and 3 mod 4 associated with primes in A007351 (the zero beginning the sequence indicates the prime 2).at n=24A092198
• a(n) = Sum_{k=0..[n/2]} C(2^k + n-2k-1, n-2k); equals the antidiagonal sums of triangle A137153.at n=13A137155
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 0), (0, 1, -1), (0, 1, 1), (1, -1, 1)}.at n=9A148898
• S_9 sequence in partition of integers > 1 described in A240521.at n=42A240536
• Semiprimes whose prime factors are of equal binary length and which differ from each other in exactly two bit positions.at n=50A261074
• Sequence of pairwise relatively prime numbers of class P_8 (see comment in A275246).at n=17A275253
• Numbers such that the sum of the reverse of their aliquot parts is equal to the reverse of the sum of their aliquot parts.at n=26A278948
• Smallest semiprime p1*p2 such that p2 mod p1 = n and no prime is used more than once in the sequence.at n=15A386256