A201627 E.g.f. satisfies: A(x) = 1/(1 - sin(x*A(x))).

1, 1, 4, 29, 312, 4481, 80768, 1754549, 44647040, 1303097665, 42923116032, 1575332861101, 63754405679104, 2820829737123841, 135469202252333056, 7018336152909163205, 390175030207597805568, 23169468447962190613121, 1463683656780476860989440, 98016257612539018485477821

Offset

0,3

Comments

Coefficients in the expansion of 1/(1-sin(x)) yield the Euler numbers (A000111).

Links

Table of n, a(n) for n=0..19.

Formula

E.g.f. A(x) satisfies: A( x*(1 - sin(x)) ) = 1/(1 - sin(x)).

E.g.f.: (1/x)*Series_Reversion( x*(1 - sin(x)) ).

a(n) = [x^n] 1/(1 - sin(x))^(n+1) / (n+1).

a(n) = A214222(n+1)/(n+1).

Example

E.g.f.: A(x) = 1 + x + 4*x^2/2! + 29*x^3/3! + 312*x^4/4! + 4481*x^5/5! +...
The coefficients in initial powers of G(x) = 1/(1 - sin(x)) begin:
G^1: [(1), 1, 2, 5, 16, 61, 272, 1385, 7936, ..., A000111(n+1), ...];
G^2: [1,(2), 6, 22, 96, 482, 2736, 17302, ...];
G^3: [1, 3,(12), 57, 312, 1923, 13152, 98697, ...];
G^4: [1, 4, 20,(116), 760, 5524, 44000, 380516, ...];
G^5: [1, 5, 30, 205,(1560), 13025, 118080, 1153105, ...];
G^6: [1, 6, 42, 330, 2856,(26886), 272832, 2963850, ...];
G^7: [1, 7, 56, 497, 4816, 50407, (565376), 6754097, ...];
G^8: [1, 8, 72, 712, 7632, 87848, 1078272,(14036392), ...]; ...
where coefficients in parenthesis form initial terms of this sequence:
[1/1, 2/2, 12/3, 116/4, 1560/5, 26886/6, 565376/7, 14036392/8, ...].

Prog

(PARI) {a(n)=n!*polcoeff(1/x*serreverse(x*(1-sin(x+x^2*O(x^n)))), n)}
(PARI) {a(n)=n!*polcoeff(1/(1-sin(x+x*O(x^n)))^(n+1)/(n+1), n)}

Crossrefs

Cf. A214222, A201594, A000111.

Sequence in context: A014622 A030019 A303928 * A195194 A215955 A295237

Adjacent sequences: A201624 A201625 A201626 * A201628 A201629 A201630

Keyword

nonn

Author

Paul D. Hanna, Dec 03 2011

Status

approved