programlibs/Numbers/demos/primes.xtl

Primes: twin primes, Goldbach's conjecture and perfect numbers, each one array expression. Run with "just demo Numbers primes".

source · imports n: libs/Numbers/src/Numbers.xtl

p : Int

value · line 6
p ← ⁿp̲rimes 200
Used in: twin, ᵘg̲oldbach

twin : Int

value · line 9
twin ← (2 = (1 d̲rop p) − -1 d̲rop p) r̲eplicate -1 d̲rop p
Used in: libs/Numbers/demos/primes.xtl:10

ᵘg̲oldbach : Int -> Int

function · line 14
ᵘg̲oldbach ← { e → q ← (p ≤ e d̲iv 2) r̲eplicate p◆ t̲ally w̲here ⁿp̲rime? e − q }
Used in: libs/Numbers/demos/primes.xtl:15

v : Int

value · line 18
v ← 1 d̲rop r̲ange 1000
Used in: s, libs/Numbers/demos/primes.xtl:20

s : Int

value · line 19
s ← '{ ('+ r̲/ ⁿd̲ivisors ⍵) − ⍵ } e̲ach v
Used in: libs/Numbers/demos/primes.xtl:20