CD4017 document in PDF form, 81.0 KB, for the CMOS decade counter with ten decoded outputs. Though tagged as a schematic, it is likely the datasheet listing pinout, reset and clock-enable behaviour and timing. It is handy when a sequencing or chaser circuit stalls: verify the clock arrives, the reset pin sits low, and outputs step in order. The sheet also confirms output pin numbering, which differs from count order, and helps cross-reference HCF4017 or HEF4017 versions.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
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The standard format for schematics, block diagrams, power-sequence charts and service manuals.