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A307890 Prime centuries with at least one prime year in each decade and exactly one prime year in decades 1 to 8. 1
3677, 4073, 16447, 118463, 211217, 357131, 368153, 582017, 932413, 1172777, 1239443, 2284027, 2421473, 3900931, 4943777, 5046053, 6850463, 6966059, 8046347, 10448783, 11548777, 12849937, 15198811, 16031237, 17315087, 19443679, 20075687, 20434811, 20462861, 20614667 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

In other words, prime numbers p such that there are ten consecutive primes between p*100-100 and p*100, each of them in a different decade. (The P-div-10s are all different.) - Don Reble (djr(AT)nk.ca) May 02 2019

LINKS

Table of n, a(n) for n=1..30.

EXAMPLE

4073 is in the sequence, representing the prime sequence 407203, 407207, 407219, 407221, 407233, 407249, 407257, 407263, 407273, 407287, 407291, 407299, with 2 primes in decades 0 and 9, and 1 prime in decades 1 to 8. - R. J. Mathar, May 03 2019

MAPLE

isA307890 := proc(n)

    local p, dec ;

    if not isprime(n) then

        false;

    else

        p := 100*(n-1) ;

        p := prevprime(p+10) ;

        for dec from 0 to 9 do

            if modp(floor(p/10), 10) <> dec then

                return false;

            end if;

            p := nextprime(p) ;

        end do:

        true ;

    end if;

end proc:

for i from 1 do

    p := ithprime(i) ;

    if isA307890(p) then

        printf("%d, \n", p) ;

    end if;

end do: # R. J. Mathar, May 03 2019

CROSSREFS

Cf. A156115, super set of the primes in A103608.

Sequence in context: A250895 A216139 A250702 * A103608 A204757 A250875

Adjacent sequences:  A307887 A307888 A307889 * A307891 A307892 A307893

KEYWORD

nonn,less

AUTHOR

Zak Seidov, Feb 27 2009

STATUS

approved

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Last modified September 24 22:49 EDT 2022. Contains 356949 sequences. (Running on oeis4.)