0,2

a(n)=5^n+3^n-2^n.

a(4)=690 because 5^4=625, 3^4=81, 2^4=16 and we can write 625+81-16=690.

Cf. A000079, A000244, A000351, A001047.

Adjacent sequences: A135157 A135158 A135159 this_sequence A135161 A135162 A135163

Sequence in context: A030192 A026376 A026899 this_sequence A046945 A089817 A006320

easy,nonn

Omar E. Pol (info(AT)polprimos.com), Nov 21 2007