

A283454


The square root of the smallest square referenced in A249025 (Numbers k such that 3^k  1 is not squarefree).


3



2, 2, 11, 2, 2, 2, 2, 2, 11, 2, 2, 2, 2, 2, 11, 2, 2, 2, 2, 2, 11, 2, 2, 13, 2, 2, 2, 11, 2, 2, 2, 2, 2, 11, 2, 2, 2, 2, 2, 11, 2, 2, 2, 2, 2, 11, 2, 2, 2, 2, 2, 11, 2, 2, 2, 2, 2, 11, 2, 2, 2, 2, 2, 11, 2, 2, 2, 2, 2, 11, 2, 13, 2, 2, 2, 2, 11, 2, 2, 2, 2, 2, 11
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OFFSET

1,1


COMMENTS

The terms are the smallest prime whose square divides 3^k1, when it is not squarefree.


LINKS

Michel Marcus, Table of n, a(n) for n = 1..121


EXAMPLE

A249025(3)=5, 3^51 = 242 = 2*11*11. 242 is not squarefree the square being 11*11 = 121, the root being 11.


PROG

(PARI) lista(nn) = {for (n=1, nn, if (!issquarefree(k = 3^n1), f = factor(k/core(k)); vsq = select(x>((x%2) == 0), f[, 2], 1); print1(f[vsq[1], 1], ", "); ); ); } \\ Michel Marcus, Mar 11 2017


CROSSREFS

Cf. A046027, A249025, A249739, A283453.
Sequence in context: A081088 A236369 A001038 * A027623 A037234 A141651
Adjacent sequences: A283451 A283452 A283453 * A283455 A283456 A283457


KEYWORD

nonn


AUTHOR

Robert Price, Mar 07 2017


EXTENSIONS

More terms from Michel Marcus, Mar 11 2017


STATUS

approved



