Easter date algorithms (c) Henk Reints

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Algorithm by Jean Baptiste Joseph Delambre (1749-1822). Source: http://www.geocities.com/CapeCanaveral/4274/easter.htm NOTE: This algorithm is better known as Butcher's algorithm (published in 1876) who itself got it from an anonymous article in Nature.
Julian method (any year since A.D. 1)	Gregorian method (any year since 1583)
A = year MOD 19
B = year MOD 7	B = year DIV 100
C = year MOD 4	C = year MOD 100
D = (19 x A + 15) MOD 30	D = B DIV 4
E = (2 x C + 4 x B - D + 34) MOD 7	E = B MOD 4
result = 22 + D + E	F = (B + 8) DIV 25
	G = (B - F + 1) DIV 3
	H = (19 x A + B - D - G + 15) MOD 30
	I = C DIV 4
	K = C MOD 4
	L = (32 + 2 x E + 2 x I - H - K) MOD 7
	M = (A + 11 x H + 22 x L) DIV 451
	result = 22 + H + L - 7 x M

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Easter date algorithms (c) Henk Reints