Challenge: Generate a 64 in the display (RPN)

[Valentin Albillo]

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Hi, all:

I think it's well past the deadline so I'm posting here my solutions in the clear, but first of all let me say that when issuing or taking a challenge, the wording is essential, you should mean non-ambiguously exactly what you mean if you're issuing the challenge and you should read exactly what was written when taking it.

Gene says classic (not "Classic", "The Classics (1972)", etc.) and Gene says steps, not keystrokes, etc.

For the HP42S (and some models of HP-41), my 2-step solution is:

      01 "@"
      02 ATOX

For the HP-25 and many, many other models my 7-step solutions are:

      PI, ENTER, y^x, PI, SQRT, *, INT

or

      CLX, EXP, EXP, PI, *, INT, X^2


Nice little challenge, Gene, thank you !

Regards.
V.