A106588 Difference between n-th prime squared and n-th perfect square.

3, 5, 16, 33, 96, 133, 240, 297, 448, 741, 840, 1225, 1512, 1653, 1984, 2553, 3192, 3397, 4128, 4641, 4888, 5757, 6360, 7345, 8784, 9525, 9880, 10665, 11040, 11869, 15168, 16137, 17680, 18165, 20976, 21505, 23280, 25125, 26368, 28329, 30360

Offset

1,1

Links

G. C. Greubel, Table of n, a(n) for n = 1..1000

Formula

a(n) = prime(n)^2 - n^2.

Example

a(5) = 96 because 121 (fifth prime^2) - 25 (fifth square) = 96.

Mathematica

Table[Prime[n]^2 - n^2, {n, 50}]

Prog

(Magma) [NthPrime(n)^2 - n^2: n in [1..50]]; // G. C. Greubel, Sep 07 2021
(Sage) [nth_prime(n)^2 - n^2 for n in (1..50)] # G. C. Greubel, Sep 07 2021
(PARI) a(n) = prime(n)^2 - n^2; \\ Michel Marcus, Sep 08 2021

Crossrefs

Cf. A000290, A001248, A014688, A075526, A076368.

Sequence in context: A295358 A369930 A077551 * A123785 A121646 A226205

Adjacent sequences: A106585 A106586 A106587 * A106589 A106590 A106591

Keyword

easy,nonn

Author

Alexandre Wajnberg, May 10 2005

Extensions

Extended by Ray Chandler, May 13 2005

Status

approved