A088027 - OEIS

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A088027

Smallest square k such that k-1 is a squarefree number with n prime divisors.

4, 16, 196, 1156, 64516, 440896, 26173456, 340254916, 14809429636, 787326134596, 56199671262736, 3984666393117796, 468395620836767716, 9526636662047700196, 659973251187594258916, 205358215375529739638116

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OFFSET

1,1

COMMENTS

Program for generating a(n) for large values of n is given is A088028.

LINKS

Table of n, a(n) for n=1..16.

EXAMPLE

a(4) = 1156 = 34^2 = 3*5*7*11 +1.

PROG

(PARI) a(n) = {i = 1; k = i^2; while (! issquarefree(k-1) || (omega(k-1) != n), i++; k = i^2; ); k; } \\ Michel Marcus, Apr 11 2014

CROSSREFS