A278259 Least number with the prime signature of the n-th quarter-square, a(1) = 0.

0, 1, 2, 4, 6, 4, 12, 16, 12, 4, 30, 36, 30, 4, 24, 64, 72, 16, 60, 36, 30, 4, 60, 144, 60, 4, 30, 36, 210, 36, 240, 256, 48, 4, 60, 144, 60, 4, 60, 144, 420, 36, 210, 36, 30, 4, 120, 576, 360, 16, 60, 36, 120, 64, 360, 144, 60, 4, 210, 900, 210, 4, 96, 1024, 480, 36, 210, 36, 210, 36, 1260, 1296, 180, 4, 30, 36, 210, 36, 840, 576, 120, 4, 210, 900, 210, 4, 60

Offset: 1

Author

Antti Karttunen, Nov 22 2016

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A002620, A046523.

Cf. A278254, A278256 (bisections).

Cf. also A278260.

Programs

Scheme

(define (A278259 n) (if (<= n 1) 0 (A046523 (A002620 n))))

Formula

a(1) = 0; for n > 1, a(n) = A046523(A002620(n)).