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 A077648 Initial digits of prime numbers. 13
 2, 3, 5, 7, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 4, 5, 5, 6, 6, 7, 7, 7, 8, 8, 9, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A000030(A000040(n)). MATHEMATICA Table[First[IntegerDigits[Prime[n]]], {n, 1, 120}] PROG (MAGMA) [Intseq(p)[#Intseq(p)]: p in PrimesUpTo(600)]; // Bruno Berselli, Feb 14 2013 (PARI) a(n) = digits(prime(n))[1]; \\ Michel Marcus, Feb 11 2017 CROSSREFS Cf. A000030, A000040. Sequence in context: A230200 A113493 A060420 * A033308 A134690 A295868 Adjacent sequences:  A077645 A077646 A077647 * A077649 A077650 A077651 KEYWORD base,nonn AUTHOR Labos Elemer, Nov 19 2002 STATUS approved

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Last modified July 29 17:41 EDT 2021. Contains 346346 sequences. (Running on oeis4.)