A326555 a(n) = (2^n + 3^n)^n for n>= 0.

1, 5, 169, 42875, 88529281, 1572763671875, 248679006649044049, 356333757516508153671875, 4663869092837765297703279248641, 558720643076358108093837582958513671875, 612058887069969285456490153219530731912451357649, 6117651922857367443605981033627635368555142419249951171875, 556511030566224080586773690363350894350192064787062589546222802473281

Offset: 0

Author

Paul D. Hanna, Jul 13 2019

Keywords

• nonn

Programs

Mathematica

Table[(2^n+3^n)^n,{n,0,20}] (* Harvey P. Dale, Jun 14 2025 *)

Formula

a(n) = Sum_{k=0..n} binomial(n,k) * 2^(n*k) * 3^(n*(n-k)) for n >= 0.