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A056893 Smallest prime with square excess of n. 5
2, 3, 7, 13, 41, 31, 23, 89, 73, 59, 47, 61, 113, 239, 79, 97, 593, 139, 163, 461, 277, 191, 167, 193, 281, 251, 223, 317, 353, 991, 431, 761, 433, 563, 359, 397, 521, 479, 439, 569, 617, 571, 619, 773, 829, 887, 947, 673, 1493, 1571, 727, 1013, 953, 1279 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..54.

FORMULA

a(n) =n+A056894(n).

a(n) = min{p in A000040: A053186(p) = n}. - R. J. Mathar, Jul 28 2013

EXAMPLE

a(4)=13 since 13=3^2+4, while 2, 3, 5, 7 and 11 have square excesses of 1, 2, 1, 3 and 3 respectively.

MAPLE

A056893 := proc(n)

    local p ;

    p :=2 ;

    while A053186(p) <> n do

        p := nextprime(p) ;

    end do:

    return p ;

end proc: # R. J. Mathar, Jul 28 2013

PROG

(PARI) A056893(n)={

    local(p=2) ;

    while( A053186(p)!=n,

        p=nextprime(p+1)

    ) ;

    return(p)

} /* R. J. Mathar, Jul 28 2013 */

CROSSREFS

Cf. A053186, A000196, A002496, A048760, A056892-A056898.

Sequence in context: A013917 A293994 A196419 * A051130 A078749 A046062

Adjacent sequences:  A056890 A056891 A056892 * A056894 A056895 A056896

KEYWORD

nonn

AUTHOR

Henry Bottomley, Jul 05 2000

STATUS

approved

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Last modified June 15 01:41 EDT 2021. Contains 345041 sequences. (Running on oeis4.)