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 A116066 Numbers k such that both k and the k-th prime have nondecreasing digits. 4
 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 15, 17, 19, 22, 24, 33, 34, 35, 37, 39, 46, 48, 49, 55, 57, 59, 68, 69, 77, 88, 123, 188, 189, 222, 229, 237, 239, 246, 247, 249, 266, 278, 333, 336, 337, 345, 346, 348, 355, 357, 367, 388, 477, 489, 499, 669, 1117, 1346, 1347, 1348 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Michael S. Branicky, Table of n, a(n) for n = 1..97 (all terms < 10^9) EXAMPLE p(237) = 1489. MATHEMATICA Select[Range[1500], Min[Differences[IntegerDigits[#]]]>=0&&Min[ Differences[ IntegerDigits[Prime[#]]]]>=0&] (* Harvey P. Dale, May 14 2019 *) PROG (Python) from sympy import sieve from itertools import count, islice, combinations_with_replacement as mc def nd(n): s = str(n); return s == "".join(sorted(s)) def bgen(d): yield from map(int, ("".join(m) for m in mc("123456789", d))) def agen(): for d in count(1): yield from (k for k in bgen(d) if nd(sieve[k])) print(list(islice(agen(), 60))) # Michael S. Branicky, Jun 26 2022 CROSSREFS Cf. A116067, A116068, A116069. Sequence in context: A171827 A322002 A107743 * A261874 A334929 A008816 Adjacent sequences: A116063 A116064 A116065 * A116067 A116068 A116069 KEYWORD nonn,base AUTHOR Giovanni Resta, Feb 13 2006 STATUS approved

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Last modified August 13 13:49 EDT 2024. Contains 375142 sequences. (Running on oeis4.)