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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
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
H. Gupta, On a conjecture of Chowla, Proc. Indian Acad. Sci., 5A (1937), 381-384. [Annotated scanned copy]
MATHEMATICA
Join[{0}, Select[Table[(p^2-1)/120, {p, Prime[Range[200]]}], IntegerQ]] (* Harvey P. Dale, Jan 14 2020 *)
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 A366783 A051211
KEYWORD
nonn
EXTENSIONS
More terms from Jason Earls, Jul 29 2001
STATUS
approved

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