A187717 a(n) = A001676(n) / A187595(n).

1, 1, 1, 1, 1, 1, 1, 2, 4, 6, 1, 1, 3, 2, 2, 2, 8, 16, 2, 24, 4, 4, 48, 2, 2, 12, 1, 2, 3, 3, 4, 8, 16, 32, 4, 6, 12, 120, 96, 192, 16, 96, 1, 8, 5760, 48, 96, 32, 6, 24, 16, 24, 16, 8, 3, 1, 4, 4, 4, 4, 1, 24, 16

Offset

1,8

Comments

The quotient of |Theta_n| and |bP_(n+1)| in the 1961 Kervaire-Milnor theorem.

The quotient of |S_n| and |S_n^{bp}| in the 2011 Milnor survey (see Theorem 5, Further Details, and Table 2). - Jonathan Sondow, Jun 16 2011

Links

Table of n, a(n) for n=1..63.

Michel A. Kervaire and John W. Milnor, Groups of homotopy spheres: I, 1963

Michel A. Kervaire and John W. Milnor, Groups of homotopy spheres: I. Ann. of Math. (2) 77 1963, 504-537.

John W. Milnor, Differential Topology Forty-six Years Later, Notices Amer. Math. Soc. 58 (2011), 804-809.

John W. Milnor, Spheres, Abel Prize lecture (video), 2011.

Wikipedia, Exotic sphere

Crossrefs

Sequence in context: A013082 A352639 A197388 * A125944 A077069 A261596

Adjacent sequences: A187714 A187715 A187716 * A187718 A187719 A187720

Keyword

nonn,hard

Author

Paul Muljadi, Mar 18 2011

Extensions

More terms from Jonathan Sondow, Jun 16 2011

Terms a(56), a(57), a(63) corrected by Andrey Zabolotskiy, Nov 27 2022

Status

approved