A362406 Denominators of the expansion of the series reversion of sin(x) + x, odd powers only.
2, 96, 1920, 1290240, 92897280, 326998425600, 51011754393600, 85699747381248000, 23310331287699456000, 63777066403145711616000, 26786367889321198878720000, 867449737727777704488468480000, 520469842636666622693081088000000, 5845917272495039506088686780416000000
Offset: 0
Examples
f^-1(x) = (1/2)*x + (1/96)*x^3 + (1/1920)*x^5 + (43/1290240)*x^7 + ...
Programs
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PARI
a(n) = denominator(polcoef(serreverse(sin(x + O(x^(2*n))) + x), 2*n-1)) \\ Andrew Howroyd, Apr 18 2023
Formula
Conjecture: a(n) = 2*A306254(n)/(4^(n+1)).