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A167657 Product of n-th block of identical consecutive values of A000720. 2
0, 1, 4, 9, 256, 25, 1296, 49, 4096, 531441, 100, 1771561, 20736, 169, 38416, 11390625, 16777216, 289, 34012224, 130321, 400, 85766121, 234256, 148035889, 110075314176, 390625, 676, 531441, 784, 707281, 478296900000000000000, 923521 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Jason Kimberley, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = n^(A000040(n+1)-A000040(n)). - Jason Kimberley, May 27 2018

MAPLE

A000720 := proc(n) numtheory[pi](n) ; end proc: A167657 := proc(nmax) local ol, a ; ol := 0 ; a := 0 ; for n from 1 to nmax do if A000720(n) = ol then a := a*ol ; else printf("%d, ", a) ; a := A000720(n) ; end if; ol := A000720(n) ; end do ; return ; end proc: A167657(160) ; # R. J. Mathar, Jan 30 2010

MATHEMATICA

Most@ Map[Times @@ # &, Split@ Array[PrimePi, 132]] (* Michael De Vlieger, May 27 2018 *)

PROG

(MAGMA) A40:=NthPrime;

A167657:=func<n|(n-1)^(A40(n)-A40(n-1))>;

[A167657(n):n in[1..32]]; // Jason Kimberley, May 27 2018

CROSSREFS

Cf. A000720.

Sequence in context: A318615 A030074 A299122 * A175700 A035126 A178454

Adjacent sequences:  A167654 A167655 A167656 * A167658 A167659 A167660

KEYWORD

nonn,look

AUTHOR

Giovanni Teofilatto, Nov 08 2009

EXTENSIONS

a(1) = 0 and a(5) = 256 corrected by Giovanni Teofilatto, Nov 12 2009

a(17) inserted and a(20) corrected by R. J. Mathar, Jan 30 2010

Name edited by Jason Kimberley, Jul 01 2018

STATUS

approved

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Last modified December 10 23:29 EST 2019. Contains 329910 sequences. (Running on oeis4.)