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A078315 Minimal exponent in prime factorization of n*rad(n)+1, where rad=A007947 (the radical or squarefree kernel). 6
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 (list; graph; refs; listen; history; text; internal format)
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 * A288120 A156264 A249770

Adjacent sequences:  A078312 A078313 A078314 * A078316 A078317 A078318

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Nov 23 2002

STATUS

approved

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Last modified July 23 04:00 EDT 2019. Contains 325230 sequences. (Running on oeis4.)