catalan.js 1.2 KB

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  1. import { factory } from '../../utils/factory.js';
  2. var name = 'catalan';
  3. var dependencies = ['typed', 'addScalar', 'divideScalar', 'multiplyScalar', 'combinations', 'isNegative', 'isInteger'];
  4. export var createCatalan = /* #__PURE__ */factory(name, dependencies, _ref => {
  5. var {
  6. typed,
  7. addScalar,
  8. divideScalar,
  9. multiplyScalar,
  10. combinations,
  11. isNegative,
  12. isInteger
  13. } = _ref;
  14. /**
  15. * The Catalan Numbers enumerate combinatorial structures of many different types.
  16. * catalan only takes integer arguments.
  17. * The following condition must be enforced: n >= 0
  18. *
  19. * Syntax:
  20. *
  21. * math.catalan(n)
  22. *
  23. * Examples:
  24. *
  25. * math.catalan(3) // returns 5
  26. * math.catalan(8) // returns 1430
  27. *
  28. * See also:
  29. *
  30. * bellNumbers
  31. *
  32. * @param {Number | BigNumber} n nth Catalan number
  33. * @return {Number | BigNumber} Cn(n)
  34. */
  35. return typed(name, {
  36. 'number | BigNumber': function numberBigNumber(n) {
  37. if (!isInteger(n) || isNegative(n)) {
  38. throw new TypeError('Non-negative integer value expected in function catalan');
  39. }
  40. return divideScalar(combinations(multiplyScalar(n, 2), n), addScalar(n, 1));
  41. }
  42. });
  43. });