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A242473 Binomial(2p-1,p-1) modulo p^4, with p=prime(n). 3
3, 10, 126, 1716, 1332, 2198, 14740, 61732, 158172, 268280, 29792, 557184, 2343315, 2623732, 3218514, 5657327, 11911983, 12710937, 7218313, 12526886, 24119055, 18735483, 13151102, 19034164, 87616609 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A value of 1 indicates a Wolstenholme prime.

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000

MATHEMATICA

Table[Mod[Binomial[2p-1, p-1], p^4], {p, Prime[Range[30]]}] (* Harvey P. Dale, Jun 26 2017 *)

PROG

(PARI) forprime(n=2, 10^2, m=(binomial(2*n-1, n-1)%n^4); print1(m, ", "));

(Python)

from __future__ import division

from sympy import isprime

A242473_list, b = [], 1

for n in range(1, 10**4):

    if isprime(n):

        A242473_list.append(b % n**4)

    b = b*2*(2*n+1)//(n+1) # Chai Wah Wu, Jan 26 2016

CROSSREFS

Cf. A088164, A099905, A099906, A099907. Subsequence of A099908.

Sequence in context: A175079 A333430 A205389 * A282410 A290059 A062006

Adjacent sequences:  A242470 A242471 A242472 * A242474 A242475 A242476

KEYWORD

nonn

AUTHOR

Felix Fröhlich, May 26 2014

STATUS

approved

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Last modified July 30 17:21 EDT 2021. Contains 346359 sequences. (Running on oeis4.)