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 A333404 Lexicographically earliest sequence of positive distinct integers such that if a(n) steps over a(n) commas to the right, it is met by a term whose leftmost digit is prime. 3
 1, 2, 3, 5, 4, 7, 6, 8, 20, 9, 10, 11, 21, 12, 13, 22, 14, 15, 23, 16, 24, 17, 25, 18, 19, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 50, 42, 51, 52, 43, 44, 53, 45, 46, 47, 54, 48, 55, 49, 56, 57, 58, 59, 70, 60, 71, 61, 72, 62, 73, 63, 74, 64, 75, 65, 76, 66, 77, 67, 78, 68, 79, 69, 200, 80 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Carole Dubois, Table of n, a(n) for n = 1..5000 EXAMPLE a(1) = 1 steps over 1 comma and is met by the prime digit 2; a(2) = 2 steps over 2 commas and is met by the prime digit 5; a(3) = 3 steps over 3 commas and is met by the prime digit 7; a(4) = 5 steps over 5 commas and is met by the prime digit 2 (of "20"); a(5) = 4 steps over 4 commas and is met by the same prime digit 2 (of "20"); etc. CROSSREFS Cf. A333406 (same idea, but the leftmost digit of the target is nonprime) and A333324 (leftmost digit is odd). Sequence in context: A098311 A342265 A230086 * A227082 A227142 A246696 Adjacent sequences:  A333401 A333402 A333403 * A333405 A333406 A333407 KEYWORD base,nonn AUTHOR Eric Angelini and Carole Dubois, Mar 19 2020 STATUS approved

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Last modified July 25 13:05 EDT 2021. Contains 346290 sequences. (Running on oeis4.)