A078315 Minimal exponent in prime factorization of n*rad(n)+1, where rad=A007947 (the radical or squarefree kernel).

1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1

Offset

1,4

Comments

2 = a(4) = a(45) = a(48) = a(140) = a(529) = a(682) = a(3264) = a(3564) = a(4680) = a(4756) = a(166320) = a(194873) = a(330096) = a(364905) = a(2100332) = a(4160200) with all terms in between equal to 1. Is there an n with a(n) > 2? - Charles R Greathouse IV, May 20 2013

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Formula

a(n) = A051904(A078310(n)).

Prog

(PARI) a(n)=my(f=factor(n)); f[, 2]=apply(n->n+1, f[, 2]); vecmin(factor(factorback(f)+1)[, 2]) \\ Charles R Greathouse IV, May 20 2013
(Haskell)
a078315 = a051904 . a078310  -- Reinhard Zumkeller, Jul 23 2013

Crossrefs

Cf. A078314, A078316.

Sequence in context: A294619 A054977 A272901 * A365685 A346418 A288120

Adjacent sequences: A078312 A078313 A078314 * A078316 A078317 A078318

Keyword

nonn

Author

Reinhard Zumkeller, Nov 23 2002

Status

approved