nuances - How should I write "ikigai" in shodō?

I'd like to use ikigai ("something one lives for; purpose in life; raison d'être") for a calligraphy (shodō) work.

According to Tangorin there are three possible ways to write this:

1. 生き甲斐


2. 生きがい


3. 生甲斐

It's shodō, so I'd prefer to use a purely kanji version (i.e. #3) but I wonder if these are absolutely interchangeable or if there is a "preferred version" (and in that case, which one and why).

Answer

According to JWP and AEDICT (my feeling is that both use the same dictionary, so I can't be 100% sure) the correct spelling* is the following:

生【い】き甲斐【がい】 (n) something one lives for, very important, (P)

I hope that helps.

• I typed spelling because that's how my Japanese teacher used to refer to kanji composition and stroke order.

This is how you spell the kanji correctly.

or

Make sure that you use the correct kanji spelling