-99144

Appears in sequences

• Expansion of e.g.f.: sec(exp(x)-sec(x))=1+1/2!*x^2+9/4!*x^4-20/5!*x^5+177/6!*x^6...at n=9A013338
• Triangular sequence produced from symmetrical power of two matrices of the general type: M={{1, 2, 4, 8}, {2, 1, 2, 4}, {4, 2, 1, 2}, {8, 4, 2, 1}}.at n=38A129964