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A146316 Prime subtrahends of nearest squares producing prime differences 4
2, 2, 5, 3, 2, 7, 5, 2, 11, 5, 3, 2, 17, 11, 3, 17, 13, 7, 5, 2, 23, 17, 5, 3, 2, 29, 23, 17, 5, 31, 17, 13, 11, 7, 2, 17, 11, 3, 2, 41, 23, 17, 5, 29, 19, 13, 7, 5, 29, 23, 17, 3, 2, 41, 23, 11, 2, 47, 43, 41, 37, 23, 19, 17, 13, 53, 47, 41, 11, 5, 3, 2, 59, 53, 47, 5, 3, 2, 67, 59, 47, 37 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Terms in A146315 + A146316 produce a square

LINKS

Table of n, a(n) for n=1..82.

EXAMPLE

a(6)=7 because when the prime 29 is subtracted from the square 36, the result is another prime, 7

PROG

(UBASIC) 10 'sq less pr are prime 20 N=1:O=1:C=1 30 A=3:S=sqrt(N) 40 B=N\A 50 if B*A=N then 120 60 A=A+2 70 if A<=S then 40 80 R=O^2:Q=R-N 90 if N<R and N=prmdiv(N) and Q=prmdiv(Q) then print R; N; Q:N=N+2:C=C+1:goto 30 100 if C>31 then stop 120 N=N+2:if N<R then 30:else O=O+1:goto 80

CROSSREFS

A146315 A146317 A146318

Sequence in context: A076561 A132851 A293833 * A258803 A157495 A308143

Adjacent sequences:  A146313 A146314 A146315 * A146317 A146318 A146319

KEYWORD

easy,nonn

AUTHOR

Enoch Haga, Oct 30 2008

STATUS

approved

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Last modified April 5 03:58 EDT 2020. Contains 333238 sequences. (Running on oeis4.)