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A308752 Integers k such that the equation A034699(k)=x has more than one solution in the range [prevprime(k), nextprime(k)]. 3
4180, 4199, 43355, 43384, 68400, 68425, 162150, 162197, 326781, 326830, 448477, 448514, 1013948, 1013985, 1060790, 1060851, 1357216, 1357299, 1373904, 1373951, 1568800, 1568853, 1928880, 1928927, 2313685, 2313744, 8752880, 8752951, 11555804, 11555901, 11962832, 11962935, 16062201, 16062280, 23120064, 23120153 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Is it always true that a(2*n) - a(2*n-1) = A034699(2*n) = A034699(2*n-1)? - I. V. Serov, Jun 23 2019

LINKS

L. Joris Perrenet, Table of n, a(n) for n = 1..108

EXAMPLE

A034699(4180) = A034699(4199) = 19 in the range [4177, 4201].

A034699(23120064) = A034699(23120153) = 89 in [23120039, 23120171]. - I. V. Serov, Jun 23 2019

PROG

(PARI) lppf(n) = if(1==n, n, my(f=factor(n)); vecmax(vector(#f[, 1], i, f[i, 1]^f[i, 2]))); \\ A034699

lista(nn) = {for (n=1, nn, my(p = prime(n), q = nextprime(p+1)); my(v = vector(q-p-1, k, lppf(k+p)), vs = vecsort(v, , 8)); if (#v != #vs, for (i=1, #vs, my(vx = select(x->(x==vs[i]), v, 1)); if (#vx > 1, for (j=1, #vx, print1(p+vx[j], ", ")); ); ); ); ); }

CROSSREFS

Cf. A007917 (prevprime), A007918 (nextprime), A034699.

Sequence in context: A250161 A256836 A104918 * A179249 A045734 A155511

Adjacent sequences:  A308749 A308750 A308751 * A308753 A308754 A308755

KEYWORD

nonn

AUTHOR

Michel Marcus, Jun 22 2019

EXTENSIONS

a(35)-a(36) from I. V. Serov, Jun 23 2019

STATUS

approved

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Last modified October 20 15:23 EDT 2021. Contains 348111 sequences. (Running on oeis4.)