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A357776
Integer pairs that generate only odd prime sums (as described in comment).
1
1, 2, 6, 11, 12, 17, 30, 41, 72, 101, 156, 546, 1481, 3917, 11886, 14627, 27737, 78696, 118901, 137436, 1676610, 12618762, 111018431, 574060031, 47357739281, 168920413410
OFFSET
1,2
COMMENTS
Odd terms of the pairs are prime (besides 1). Sequence is extended by adding satisfactory pairs of the next larger odd, even pair, with the odds being prime and selected first for the pair. Not every prime will be seen, limited duplicates will be seen. Seeding was 1, 2, 6, 11 and final sequence is ordered.
Is the sequence infinite? Similar sequences may exist beginning with different seeds and protocols, e.g., 1, 2, 3, 4, ??.
LINKS
Bill McEachen, PARI script, corrected Bill McEachen, Oct 13 2024
EXAMPLE
From the 4 initial seeds we see sums 1 + 2, 1 + 6, 11 + 2, 11 + 6 so 1, 2, 6 and 11 are all sequence terms. We then seek the next pair; the next available prime is 13 but as 13 + 2 yields a composite, we move to 17 as the third odd candidate. Since 17 plus each existing even is prime, we move to the next even candidate, 12. We find 12 plus each of the odds 1, 11, 17 is prime, and so the third pair added is (12, 17). Repeating, the 4th pair added is (30, 41). The 5th pair added is (72, 101), and so on. Here is the table after 4 pairs:
.
Triangle T(o,e) begins:
.
o\e| 2 6 12 30 ...
---+----------------------
1| 3 7 13 31 ...
11| 13 17 23 41 ...
17| 19 23 29 47 ...
41| 43 47 53 71 ...
...
CROSSREFS
Sequence in context: A123112 A092189 A228061 * A191772 A323044 A057976
KEYWORD
nonn,base,more
AUTHOR
Bill McEachen, Oct 12 2022
STATUS
approved