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A119488
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Primes of the form (i+1.th prime)*(i+1) - (i.th prime)*i.
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1
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13, 23, 41, 83, 103, 89, 103, 113, 227, 229, 547, 373, 419, 263, 373, 787, 419, 433, 593, 563, 577, 739, 487, 811, 823, 683, 1013, 599, 1153, 641, 827, 1571, 1223, 863, 883, 719, 1567, 1187, 1279, 1999, 1361, 1373, 1951, 1297, 2477, 1091, 1399, 1117, 2897
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| The fourth prime is 7 and the third is 5.
Therefore 7*4 - 5*3 = 28 - 15 = 13 that is a prime.
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MAPLE
| P:=proc(n) local i, j; for i from 1 by 1 to n do j:=ithprime(i+1)*(i+1)-ithprime(i)*i; if isprime(j) then print(i); fi; od; end: P(200);
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CROSSREFS
| Cf. A119487.
Sequence in context: A164494 A164407 A135283 * A112394 A067227 A068712
Adjacent sequences: A119485 A119486 A119487 * A119489 A119490 A119491
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KEYWORD
| easy,nonn
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AUTHOR
| Paolo P. Lava & Giorgio Balzarotti (paoloplava(AT)gmail.com), May 23 2006
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