login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A002381 Numbers of the form (p^2 - 1)/120 where p is 1 or prime.
(Formerly M2614 N1034)
4
0, 1, 3, 7, 8, 14, 29, 31, 42, 52, 66, 85, 99, 143, 161, 185, 190, 267, 273, 304, 330, 371, 437, 476, 484, 525, 603, 612, 658, 806, 913, 1015, 1074, 1197, 1261, 1340, 1394, 1463, 1477, 1548, 1606, 1680, 1771, 1912, 2009, 2075, 2159, 2262, 2439, 2698, 2717 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

For n>1, primes p corresponding to a(n) are in A038872(n) = A045468(n-1) = A141158(n). - Ray Chandler, Jul 29 2019

REFERENCES

H. Gupta, On a conjecture of Chowla, Proc. Indian Acad. Sci., 5A (1937), 381-384.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Ray Chandler, Table of n, a(n) for n = 1..10000

H. Gupta, On a conjecture of Chowla, Proc. Indian Acad. Sci., 5A (1937), 381-384. [Annotated scanned copy]

PROG

(PARI) j=[]; for(n=0, 150, x=prime(n)^2-1; if(Mod(x, 120)==0, j=concat(j, (x/120)))); j

CROSSREFS

Cf. A002382, A002855, A038872, A045468, A141158, subsequence of A093722.

Sequence in context: A067064 A093722 A309745 * A131559 A051211 A105173

Adjacent sequences:  A002378 A002379 A002380 * A002382 A002383 A002384

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Jason Earls, Jul 29 2001

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 15 01:15 EST 2019. Contains 329142 sequences. (Running on oeis4.)