(petitioner's mistake in using tax preparation software sufficient excuse to eliminate imposition of penalties for underreporting income on tax return; petitioner failed to properly report income from trust for which wife was beneficiary and which was reported on K-1 issued to wife, but petitioner unfamiliar with Schedule K-1; petitioner had upgraded software to account for trust income, but made data entry error that barred interest income from being correctly reported; court noted that tax preparation software only as good as information that is input, and error was isolated and source of income correctly reported; court viewed petitioner's job with U.S. Department of Energy which required security clearance persuasive as it provided petitioner with substantial motivation to report income on return properly).