Peterson–Stein formula
In mathematics, the Peterson–Stein formula, introduced by Franklin P. Peterson and Norman Stein (1960), describes the Spanier–Whitehead dual of a secondary cohomology operation.
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Wikipedia
In mathematics, the Peterson–Stein formula, introduced by Franklin P. Peterson and Norman Stein (1960), describes the Spanier–Whitehead dual of a secondary cohomology operation.