public static function eulerMascheroni(): Decimal
    {
        if (null === self::$EulerMascheroni) {
            self::$EulerMascheroni = Decimal::fromString(
                "0.57721566490153286060651209008240"
            );
        }
        return self::$EulerMascheroni;
    }
public static function eulerMascheroni(): Decimal
    {
        if (null === self::$EulerMascheroni) {
            self::$EulerMascheroni = Decimal::fromString(
                "0.57721566490153286060651209008240"
            );
        }
        return self::$EulerMascheroni;
    }
public static function eulerMascheroni ( ) : Decimal { if ( null === self :: $ EulerMascheroni ) { self :: $ EulerMascheroni = Decimal :: fromString ( "0.57721566490153286060651209008240" ) ; } return self :: $ EulerMascheroni ; }
Returns the Euler-Mascheroni constant.
@return Decimal
Returns the Euler - Mascheroni constant .