Seven Queens "number to card" calculation (difficult).

Note that this thread is for other magician articles/threads to reference.

The easy "card to number" calculation is documented elsewhere on another thread. This thread is specifically on how to calculate "number to card" for the Seven Queens stack (this will also work on the Jackknife stack and the King Deuce stack).

Below is the Seven Queens stack:
7S, QD, 8D, KC, 10H, 9C, AC, 3S, 6H, 5C, JS, 2H, 4D
7H, QS, 8S, KD, 10C, 9D, AD, 3H, 6C, 5D, JH, 2C, 4S
7C, QH, 8H, KS, 10D, 9S, AS, 3C, 6D, 5S, JC, 2D, 4H
7D, QC, 8C, KH, 10S, 9H, AH, 3D, 6S, 5H, JD, 2S, 4C

Note that the possible offsets that may be used are: 0 or 13 or 26 or 39.

The Suits associated number: 1=spades, 2=hearts, 3=clubs, 4=diamonds. Note that 0 is also equal to diamonds.

Below is the Harry Riser type of twin pairs:

Ace and 7 (have a sharp angle at top)
2 and Queen (2 headed Queen)
3 and 8 (the 3 looks like half of an eight)
4 and King (the K and 4 have 4 corners)
5 and 10 (five and dime store)
6 and 9 (same symbol upside down)
Jack stands alone.

Also note that we have an imaginary 8 rung ladder with rungs numbered 0, 1, 2, 3, 0, 1, 2, 3.
This ladder will come in handy below. These rung numbers do NOT directly relate to the suits, it's the number of steps that are taken between the rungs that relate to the suits (this will be explained a little further below).

Note that the term "mod 4" just means the REMAINDER number when dividing by 4.
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A spectator names any number from one to 52.

The magician (or shill) mentally calculates:
1. Subtracts the nearest OFFSET that is lower than the named number (this gives a number from one to 13).
2. The Harry Riser type pair is the value of the card.
3. To determine the suit of the card:
a. Mod 4 the Harry Riser pair (result will be 0 or 1 or 2 or 3). From the bottom of the ladder this is the STARTING RUNG.
b. The TARGET RUNG is the first rung above that is equal to THE FIRST DIGIT OF THE OFFSET.
c. The NUMBER OF STEPS to get from the starting rung to the target rung equates to the suit value ie: 1 step=spades, 2 steps=hearts, 3 steps=clubs, 4 steps=diamonds (or zero steps equals diamonds).

The above rules work on the Seven Queens stack, Jackknife stack, and King Deuce stack.
The below examples are only for the Seven Queens stack.

Example: spectator names the number 28.
Magician or shill calculates:
Nearest lower possible offset is 26.
28 - 26 is 2
The 2's twin is the Queen (12).
Mod 4 the 12 gives 0.
How many steps to get from the 0 rung to the first digit of 26 rung (rung 2)?
We must take two steps up:
(rung 1, then rung 2).
The two steps equates to hearts.
Thus the answer is the Queen of Hearts.

Example: spectator names the number 18.
Magician or shill calculates:
Nearest lower possible offset is 13.
18 - 13 is 5
The 5's twin is the 10 (the card value).
Mod 4 the 10 gives 2.
How many steps to get from the '2" rung to the first digit of 13 rung (rung 1)?
We must take three steps up:
(rung 3, then rung 0, then rung 1).
The three steps equates to clubs.
Thus the answer is the Ten of Clubs.

Example: spectator names the number 39.
Magician or shill calculates:
Nearest lower possible offset is 26.
39 - 26 is 13
The King (13) twin is the 4 (the card value).
Mod 4 the 4 gives 0.
How many steps to get from the "0" rung to the first digit of 26 rung (rung 2)?
We must take two steps up:
(rung 1, then rung 2).
The two steps equates to hearts.
Thus the answer is the Four of Hearts.

Example: spectator names the number 6.
Magician or shill calculates:
Nearest lower possible offset is 0.
6 - 0 is 6
The 6 twin is the 9 (the card value).
Mod 4 the 9 gives 1.
How many steps to get from the "1" rung to the first digit of 0 rung (next rung 0)?
We must take three steps up:
(rung 2, then rung 3, then rung 0).
The three steps equates to clubs.
Thus the answer is the Nine of Clubs.

Example: spectator names the number 20.
Magician or shill calculates:
Nearest lower possible offset is 13.
20 - 13 is 7.
The 7's twin is the Ace (1). The card value.
Mod 4 the 1 gives 1 .
How many steps to get from the "1" rung to the first digit of 13 rung (rung 1)?
We must take zero or 4 steps up:
(rung 2, then rung 3, then rung 0, then rung 1).
The 0 or 4 steps equates to diamonds.
Thus the answer is the Ace of Diamonds.

Note that "zero steps up" or "four steps up" will get to the same target rung number thus zero or four steps up means diamonds.

Also see the below link for an easier way to do "number to card" using the spectator's fingers:

https://www.themagiccafe.com/forums/view......orum=205

The above link is in shuffled not stirred.