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A simpler proof of Jensen's coding theorem

Sy D. Friedman
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Abstract

We present a simplification of Jensen's proof of his Coding Theorem (even in the case where 0# exists). The proof avoids Jensen's split into cases according to whether or not 0# exists. In addition, the paper contains self-contained proofs of the necessary forms of Square and Diamond, based on an approach to fine structure using Jensen's $Σ^*$ theory.

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Sy D. Friedman. 1992-11-24. A simpler proof of Jensen's coding theorem. https://arxiv.org/abs/math/9211204

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