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 A348244 Indices of 1's in A307720. 2
 1, 2, 4, 6, 48, 50, 52, 54, 56, 58, 1375, 1377, 1379, 1381, 1383, 1385, 1387, 1389, 1391, 1393, 1395, 1397, 3739, 3741, 3743, 3745, 3747, 3749, 3751, 3753, 3755, 3757, 3759, 3761, 3763, 3765, 3767, 3769, 3771, 3773, 6681, 6683, 6685, 6687, 6689, 6691, 6693, 6695, 6697, 6699, 6701, 6703, 6705 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Theorem: This sequence is infinite. Proof: Every prime in A307720 is immediately preceded or followed by a 1. - N. J. A. Sloane, Oct 30 2021 The start of this sequence consists of arithmetic progressions of constant difference 2 and lengths 1, 3, 6, 12, 18, 26, 76, ... that start with 1, 2, 48, 1375, 3739, 6681, 84627, 91833, ... It would be nice to have an alternative way to explain these numbers. LINKS N. J. A. Sloane, Table of n, a(n) for n = 1..927 CROSSREFS Cf. A307720. Sequence in context: A084324 A329529 A333456 * A066220 A348152 A009257 Adjacent sequences:  A348241 A348242 A348243 * A348245 A348246 A348247 KEYWORD nonn AUTHOR N. J. A. Sloane, Oct 16 2021 STATUS approved

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Last modified December 5 10:11 EST 2021. Contains 349543 sequences. (Running on oeis4.)