Template:Sequence of the Day for June 29

Intended for: June 29, 2012

Timetable

• First draft entered by Alonso del Arte on March 28, 2011. ✓
• Draft reviewed by Daniel Forgues on April 21, 2011. ✓
• Draft approved by T. D. Noe on May 23, 2011.✓

Yesterday's SOTD * Tomorrow's SOTD

The line below marks the end of the <noinclude> ... </noinclude> section.

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A090684: Primes of the form

8 n 2  −  1

.

{ 7, 31, 71, 127, 199, 647, 967, 1151, 1567, 2311, 2591, 2887, 3527, 4231, ... }

221	223	225	227	229	231	233	235	237	239	241
219	145	147	149	151	153	155	157	159	161	163
217	143	85	87	89	91	93	95	97	99	165
215	141	83	41	43	45	47	49	51	101	167
213	139	81	39	13	15	17	19	53	103	169
211	137	79	37	11	1	3	21	55	105	171
209	135	77	35	9	7	5	23	57	107	173
207	133	75	33	31	29	27	25	59	109	175
205	131	73	71	69	67	65	63	61	111	177
203	129	127	125	123	121	119	117	115	113	179
201	199	197	195	193	191	189	187	185	183	181

In the odd number variant of the Ulam spiral, unencumbered by the even numbers, the prime numbers can line up in horizontal and vertical lines. But there are still noticeable diagonal lines of primes, and these primes fall on one such diagonal.