# $RCA_{0}$

$RCA_{0}$ is a weakened form of second order arithmetic. It consists of the axioms of PA other than induction, together with $\Sigma^{0}_{1}$ -IND and $\Delta^{0}_{1}$ -CA.

Title $RCA_{0}$ RCA0 2013-03-22 12:57:00 2013-03-22 12:57:00 Henry (455) Henry (455) 4 Henry (455) Definition msc 03F35 RCA RCA0