1 | import { factory } from '../../utils/factory.js';
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2 | var name = 'bellNumbers';
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3 | var dependencies = ['typed', 'addScalar', 'isNegative', 'isInteger', 'stirlingS2'];
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4 | export var createBellNumbers = /* #__PURE__ */factory(name, dependencies, _ref => {
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5 | var {
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6 | typed,
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7 | addScalar,
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8 | isNegative,
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9 | isInteger,
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10 | stirlingS2
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11 | } = _ref;
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12 |
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13 | /**
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14 | * The Bell Numbers count the number of partitions of a set. A partition is a pairwise disjoint subset of S whose union is S.
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15 | * bellNumbers only takes integer arguments.
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16 | * The following condition must be enforced: n >= 0
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17 | *
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18 | * Syntax:
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19 | *
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20 | * math.bellNumbers(n)
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21 | *
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22 | * Examples:
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23 | *
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24 | * math.bellNumbers(3) // returns 5
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25 | * math.bellNumbers(8) // returns 4140
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26 | *
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27 | * See also:
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28 | *
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29 | * stirlingS2
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30 | *
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31 | * @param {Number | BigNumber} n Total number of objects in the set
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32 | * @return {Number | BigNumber} B(n)
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33 | */
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34 | return typed(name, {
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35 | 'number | BigNumber': function numberBigNumber(n) {
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36 | if (!isInteger(n) || isNegative(n)) {
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37 | throw new TypeError('Non-negative integer value expected in function bellNumbers');
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38 | } // Sum (k=0, n) S(n,k).
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39 |
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40 |
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41 | var result = 0;
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42 |
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43 | for (var i = 0; i <= n; i++) {
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44 | result = addScalar(result, stirlingS2(n, i));
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45 | }
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46 |
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47 | return result;
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48 | }
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49 | });
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50 | }); |
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