A050237 - OEIS

A050237

a(n) = the smallest number m such that there are exactly n sets of consecutive primes, each of which has an arithmetic mean of m.

1, 2, 5, 12, 38, 30, 173, 165, 12259, 8803, 36735, 67263, 5296771, 32975, 1147233

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OFFSET

0,2

COMMENTS

First appearance of n in A122821.

LINKS

Table of n, a(n) for n=0..14.

EXAMPLE

a(4) = 38 because there are exactly four sets of consecutive primes which have means of 38: {31,37,41,43}, {29,...,47}, {23,...,53} and {2,...,83},

PROG

(PARI) {a(n)= m=2; starting_index=1; k=starting_index; sum_of_primes=0; prime_count=0; sets=0; until( (prime(starting_index)>m) && (sets==n), if( (prime(starting_index)> m) || (sets>n), m++; sets=0; starting_index=1; k=starting_index); sum_of_primes=sum_of_primes+prime(k); prime_count++; mean=sum_of_primes/ prime_count; if(mean<m, k++, sum_of_primes=0; prime_count=0; starting_index++; k=starting_index; if(mean==m, sets++))); return(m)} \\ Rick L. Shepherd, Jun 14 2004

CROSSREFS

Cf. A060863, A082431, A122821.

Sequence in context: A115277 A130221 A036782 * A050258 A051436 A054581

Adjacent sequences: A050234 A050235 A050236 * A050238 A050239 A050240

KEYWORD

more,nonn

AUTHOR

Naohiro Nomoto, May 08 2003

EXTENSIONS

Edited by Don Reble, Jun 17 2003

STATUS

approved