A009613 -id:A009613 - cp's OEIS frontend

A012390 Duplicate of A009613.

2, 16, 392, 21376, 1875872, 227105536, 35750690432, 7110343684096

Offset: 0

dead

A093051 Exponent of 2 in (3^n-3)*2^n.

0, 1, 4, 3, 7, 5, 8, 7, 12, 9, 12, 11, 15, 13, 16, 15, 21, 17, 20, 19, 23, 21, 24, 23, 28, 25, 28, 27, 31, 29, 32, 31, 38, 33, 36, 35, 39, 37, 40, 39, 44, 41, 44, 43, 47, 45, 48, 47, 53, 49, 52, 51, 55, 53, 56, 55, 60, 57, 60, 59, 63, 61, 64, 63, 71, 65, 68, 67, 71

Offset: 0

Ralf Stephan, Mar 16 2004

nonn

a(n) is the exponent of 2 in A009613(n), A010043(n), A010046(n), A012388(n-1), A009518(n), A012391(n-1), A012457(n-1), A012458(n-1), A012461(n-1), A012462(n-2).

Cf. A093050, A093052, A090740.

a(n)=if(n<1,0,if(n%2==0,a(n/2)+2*floor((n+2)/4)+1,n))

Recurrence: a(2n) = a(n) + [(n+1)/2] + 1, a(2n+1) = 2n+1.

a(n) = A090740(n) + n - 1, for n >= 1. - Amiram Eldar, Sep 14 2024

A024287 Expansion of sinh(tan(x)^2)/2.

Original entry on oeis.org

0, 1, 8, 196, 10688, 937936, 113552768, 17875345216, 3555171842048, 875294104443136, 261970132442851328, 93711886717539460096, 39452759032211774455808, 19284289193322067327799296

Offset: 0

R. H. Hardin

nonn

A009613.

Mathematica
```
Sinh[ Tan[ x ]^2 ]/2 (* Even Part *)
```

Extended and signs tested 03/97.

cp's OEIS Frontend

A012390 Duplicate of A009613.

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A093051 Exponent of 2 in (3^n-3)*2^n.

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A024287 Expansion of sinh(tan(x)^2)/2.

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