A139813 - OEIS

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A139813 as a triangular array

											1
										2		2
									2		2		2
								2		6		6		2
							2		8		6		8		2
						2		10		20		20		10		2
					2		12		30		20		30		12		2
				2		14		42		70		70		42		14		2
			2		16		56		112		70		112		56		16		2
		2		18		72		168		252		252		168		72		18		2
	2		20		90		240		420		252		420		240		90		20		2

A139813 as a square array

1	2	2	2	2	2	2	2	2	2	2
2	2	6	8	10	12	14	16	18	20
2	6	6	20	30	42	56	72	90
2	8	20	20	70	112	168	240
2	10	30	70	70	252	420
2	12	42	112	252	252
2	14	56	168	420
2	16	72	240
2	18	90
2	20
2

A139813 as an upper right triangle

1	2	2	2	2	2	2	2	2	2	2
	2	2	6	8	10	12	14	16	18	20
		2	6	6	20	30	42	56	72	90
			2	8	20	20	70	112	168	240
				2	10	30	70	70	252	420
					2	12	42	112	252	252
						2	14	56	168	420
							2	16	72	240
								2	18	90
									2	20
										2