0,2

Decimal expansions (before rounding) of Pi (A000796), Pi^Pi (A073233) and Pi^Pi^Pi (A073234) correspond to a(1), a(2) and a(3), respectively. All four terms are equivalent if floor is used instead of round. See A073237 for same sequence but using ceiling. This sequence is the analogue of A004002, which deals with e.

a(n) = round(Pi^Pi^...^Pi), where Pi occurs n times, a(0) = 1 (=Pi^0).

(PARI) p=0; for(n=0, 3, p=Pi^p; print1(round(p), ", ")) n=4 produces too large an exponent for PARI.

Cf. A000796 (Pi), A073233 (Pi^Pi), A073234 (Pi^Pi^Pi), A073237 (Ceiling of Pi^Pi^...^Pi, n times), A004002 (Benford numbers).

Sequence in context: A088322 A080807 A006268 this_sequence A002563 A140448 A128061

Adjacent sequences: A073233 A073234 A073235 this_sequence A073237 A073238 A073239

nonn

Rick L. Shepherd (rshepherd2(AT)hotmail.com), Jul 25 2002