A076601 a(1)=3, a(n_even)=(a(n-1)^2-1)/2; a(n_odd)=a(n-1)+1.

3, 4, 5, 12, 13, 84, 85, 3612, 3613, 6526884, 6526885, 21300113901612, 21300113901613, 226847426110843688722000884, 226847426110843688722000885, 25729877366557343481074291996721923093306518970391612, 25729877366557343481074291996721923093306518970391613

Offset: 1

Author

Zak Seidov, Oct 21 2002

Keywords

• easy
• nonn

Comments

{3, 4, 5}, {5, 12, 13}, {13, 84, 85}... are sides {a

Programs

Mathematica

Transpose[NestList[{#[[1]]+1,If[EvenQ[#[[1]]+1],(#[[2]]^2-1)/2,#[[2]]+1]}&,{1,3},20]][[2]] (* Harvey P. Dale, May 02 2012 *)

Extensions

More terms from Harvey P. Dale, May 02 2012

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