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A062703 Squares which are the sum of two consecutive primes. 6
36, 100, 144, 576, 1764, 2304, 3844, 5184, 7056, 8100, 12100, 14400, 14884, 30276, 41616, 43264, 48400, 53824, 57600, 69696, 93636, 106276, 112896, 138384, 148996, 166464, 168100, 197136, 206116, 207936, 219024, 220900, 224676, 272484, 298116 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harry J. Smith, Table of n, a(n) for n=1,...,100

FORMULA

A074924^2.

EXAMPLE

prime(7)+ prime(8)= 17 + 19= 36 = 6^2.

MATHEMATICA

PrevPrim[n_] := Block[{k = n - 1}, While[ !PrimeQ[k], k-- ]; k]; NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; f[n_] := Block[{m = Floor[n/2]}, s = PrevPrim[m] + NextPrim[m]; If[s == n, True, False]]; Select[ Range[550], f[ #^2] &]^2

PROG

(PARI) je=[]; for(n=1, 39000, if(issquare(prime(n)+prime(n+1)), je=concat(je, prime(n)+prime(n+1)))); je

(PARI) { n=0; for (m=1, 10^9, if(issquare(a=prime(m) + prime(m + 1)), write("b062703.txt", n++, " ", a); if (n==100, break)) ) } [From Harry J. Smith, Aug 09 2009]

(PARI) {for(n=1, 100, (p=precprime(n^2/2))+nextprime(p+2) = = n^2&

print1(n^2", "))}[Zak Seidov, Feb 17 2011]

CROSSREFS

Cf. A080665.

Sequence in context: A131605 A063734 A069057 * A043438 A044223 A044604

Adjacent sequences:  A062700 A062701 A062702 * A062704 A062705 A062706

KEYWORD

easy,nonn

AUTHOR

Jason Earls (zevi_35711(AT)yahoo.com), Jul 11 2001

EXTENSIONS

Edited by Robert G. Wilson v, Mar 02 2003

STATUS

approved

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Last modified June 18 18:23 EDT 2013. Contains 226355 sequences.