* @param y1 > 1
     * @param decimalPlaces
     * @param a_RoundingMode
     * @return
     */
    @Deprecated
    private static BigDecimal power1(
            BigDecimal x,
            int y,
            int decimalPlaces,
            RoundingMode a_RoundingMode) {
        if (y < 4) {
            return power(
                    x,
                    y,
                    decimalPlaces,
                    a_RoundingMode);
        }
        int party0 = y / 4;
        BigDecimal result = power1(
                x,
                party0,
                decimalPlaces,
                a_RoundingMode);
        result = power(
                result,
                4,
                //a_MathContext,
                decimalPlaces,
                a_RoundingMode);
        int party1 = y % 4;
        if (party1 != 0) {
            BigDecimal resultRemainder = power(
                    x,
                    party1,
                    //a_MathContext,
                    decimalPlaces,
                    a_RoundingMode);
            result = multiplyRoundIfNecessary(
                    result,
                    resultRemainder,
                    decimalPlaces,
                    a_RoundingMode);
        }
        return result;
    }