Riordan numbers: Difference between revisions
Add Scala implementation
(→{{header|Bracmat}}: Added a solution.) |
(Add Scala implementation) |
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1: { #1d #0d #1d #1d #3d #6d #15d #36d #91d #232d #603d #1585d #4213d 11298d #30537d #83097d #227475d #625992d #1730787d #4805595d #13393689d #37458330d #105089229d #295673994d #834086421d #2358641376d #6684761125d #18985057351d #54022715451d #154000562758d #439742222071d #1257643249140d }
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=={{header|Scala}}==
{{trans|Java}}
<syntaxhighlight lang="Scala">
import java.math.BigInteger
import scala.collection.mutable.ArrayBuffer
object RiordanNumbers extends App {a
val limit = 10000
val THREE = BigInteger.valueOf(3)
val riordans: ArrayBuffer[BigInteger] = ArrayBuffer.fill(limit)(BigInteger.ZERO)
riordans(0) = BigInteger.ONE
riordans(1) = BigInteger.ZERO
for (n <- 2 until limit) {
val term = BigInteger.TWO.multiply(riordans(n - 1)).add(THREE.multiply(riordans(n - 2)))
riordans(n) = BigInteger.valueOf(n - 1).multiply(term).divide(BigInteger.valueOf(n + 1))
}
println("The first 32 Riordan numbers:")
for (i <- 0 until 32) {
print(f"${riordans(i)}%14d")
if (i % 4 == 3) println()
else print(" ")
}
println()
List(1000, 10000).foreach { count =>
val length = riordans(count - 1).toString.length
println(s"The ${count}th Riordan number has $length digits")
}
}
</syntaxhighlight>
{{out}}
<pre>
The first 32 Riordan numbers:
1 0 1 1
3 6 15 36
91 232 603 1585
4213 11298 30537 83097
227475 625992 1730787 4805595
13393689 37458330 105089229 295673994
834086421 2358641376 6684761125 18985057351
54022715451 154000562758 439742222071 1257643249140
The 1000th Riordan number has 472 digits
The 10000th Riordan number has 4765 digits
</pre>
=={{header|SETL}}==
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