19193

Appears in sequences

• Consider Pythagorean triples which satisfy X^2+(X+7)^2=Z^2; sequence gives increasing values of Z.at n=9A060569
• Geometric mean of the digits = 3. In other words, the product of the digits is = 3^k where k is the number of digits.at n=40A061427
• Consider all Pythagorean triples (X,X+7,Z); sequence gives Z values.at n=15A076294
• 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, 0), (-1, 0, -1), (0, 1, 1), (1, 0, 1), (1, 1, 0)}.at n=7A151143
• a(0)=-4, a(1)=5; thereafter a(n) = 2*a(n-1) + a(n-2).at n=11A221174
• a(n) = ( 2*n*(2*n^2 + 9*n + 14) + (-1)^n - 1 )/16.at n=41A248851
• A special solution of X(n)^2 - 280*Y(n)^2 = 3^(2*n), n >= 0; here the X member.at n=3A249862
• Part of the positive proper solutions y of the Pell equation x^2 - 2*y^2 = - 7^2 based on the fundamental solution (x0, y0)= (1, 5).at n=5A254759
• Numbers n such that 3n appears earlier than 2n in A280864.at n=42A280755
• The sixth Euler transform of the sequence with g.f. 1+x.at n=8A290355
• Number of 8-leaf rooted trees with n levels.at n=6A290362
• Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-2)*b(n-1)*b(n), where a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4, b(2) = 5, and (a(n)) and (b(n)) are increasing complementary sequences.at n=10A296279
• Number of Golomb partitions of n.at n=46A325858
• Breadth-first reading of the subtree rooted at 5 of the tree where each parent node is the arithmetic derivative (A003415) of all its children.at n=20A327975