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Abstract
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In this note we prove the
following theorems.
Theorem A. Let Mn be a spin manifold with n ≡ 7 mod 8 and n > 7. Then M
admits at least 8 nonhomotopic tangent 4-frame fields.
Theorem B. Let Mn be a spin manifold with n ≡ 3 mod 8 and n > 3. Suppose that
wn−4M = 0 and w4M ⋅ wn−5M = 0. Then Mn admits a tangent 4-frame field
iff
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Mathematical Subject Classification
Primary: 57D25, 57D25
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Milestones
Received: 1 August 1977
Published: 1 May 1978
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