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A077767 Number of primes of form 4k+3 between n^2 and (n+1)^2. 4
1, 1, 1, 2, 1, 2, 1, 3, 1, 2, 3, 3, 2, 3, 3, 3, 2, 3, 3, 3, 4, 5, 3, 4, 4, 4, 3, 5, 4, 4, 5, 5, 4, 4, 5, 5, 4, 8, 8, 5, 4, 6, 5, 6, 7, 5, 5, 7, 5, 7, 7, 7, 6, 8, 4, 5, 11, 5, 9, 8, 6, 11, 7, 7, 7, 7, 8, 10, 5, 12, 10, 5, 9, 10, 7, 13, 8, 8, 11, 5, 10, 9, 13, 9, 6, 9, 12, 7, 7, 11, 10, 9, 12, 11, 10, 10 (list; graph; refs; listen; history; internal format)
OFFSET

1,4

COMMENTS

Related to Legendre's conjecture that there is always a prime between two consecutive squares.

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

EXAMPLE

a(8)=3 because primes 67, 71 and 79 are between squares 64 and 81

MATHEMATICA

maxN=100; a=Table[0, {maxN}]; maxP=PrimePi[(maxN+1)^2]; For[i=1, i<=maxP, i++, p=Prime[i]; If[Mod[p, 4]==3, j=Floor[Sqrt[p]]; a[[j]]++ ]]; a

CROSSREFS

Cf. A002145, A014085, A077766.

Sequence in context: A060135 A057112 A071956 * A137163 A072625 A090329

Adjacent sequences:  A077764 A077765 A077766 * A077768 A077769 A077770

KEYWORD

nonn

AUTHOR

T. D. Noe (noe(AT)sspectra.com), Nov 20 2002

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Last modified February 17 13:28 EST 2012. Contains 206031 sequences.