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A334027 "Look and say" the concatenated exponents in the prime factorization of n. 0
10, 11, 11, 12, 11, 21, 11, 13, 12, 21, 11, 1211, 11, 21, 21, 14, 11, 1112, 11, 1211, 21, 21, 11, 1311, 12, 21, 13, 1211, 11, 31, 11, 15, 21, 21, 21, 22, 11, 21, 21, 1311, 11, 31, 11, 1211, 1211, 21, 11, 1411, 12, 1112, 21, 1211, 11, 1113, 21, 1311, 21, 21, 11, 1221, 11 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..61.

Eric Weisstein's World of Mathematics, Look and Say Sequence

Wikipedia, Look-and-say sequence

FORMULA

a(n) = A045918(A037916(n)).

EXAMPLE

2 = 2^1 and there is one 1, so a(2) = 11.

3 = 3^1 and there is one 1, so a(3) = 11.

4 = 2^2 and there is one 2, so a(4) = 12.

5 = 5^1 and there is one 1, so a(5) = 11.

6 = 2^1*3^1 and there are two 1's, so a(6) = 21.

7 = 7^1 and there is one 1, so a(7) = 11.

8 = 2^3 and there is one 3, so a(8) = 13.

9 = 3^2 and there is one 2, so a(9) = 12.

10 = 2^1*5^1 and there are two 1's, so a(10) = 21.

CROSSREFS

Cf. A037916, A045918.

Sequence in context: A065016 A087381 A136400 * A121266 A045988 A008947

Adjacent sequences:  A334024 A334025 A334026 * A334028 A334029 A334030

KEYWORD

nonn,base

AUTHOR

Wesley Ivan Hurt, Apr 12 2020

STATUS

approved

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Last modified December 4 11:50 EST 2021. Contains 349486 sequences. (Running on oeis4.)