The standard PDP alphanumeric paper tape code includes an odd parity bit which may be checked by the program.
"Preliminary Specifications: Programmed Data Processor Model Three (PDP-3)" by Digital Equipment Corporation
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LDPC codes are homogeneous Boolean linear systems where parity checks and variables may have arbitrary degree distributions, with the restriction that variables should always have degrees no less than 2.
Geometrical organization of solutions to random linear Boolean equations
For example, some ﬁnite geometry LDPC codes require a redundant parity check matrix to achieve good decoding performance with BP.
Average Stopping Set Weight Distribution of Redundant Random Matrix Ensembles
The average stopping set weight distributions presented in and are a useful decoding performance measure (for BP on BEC) of a given ensemble of parity check matrices.
Average Stopping Set Weight Distribution of Redundant Random Matrix Ensembles
Redundant extension of a parity check matrix.
Average Stopping Set Weight Distribution of Redundant Random Matrix Ensembles
It becomes difﬁcult to evaluate the number of extended parity check matrices giving a stopping set for a given weight when L > 2.
Average Stopping Set Weight Distribution of Redundant Random Matrix Ensembles
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