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A251720
a(n) = (p_n)^2 * p_{n+1}, where p_n is the n-th prime, A000040(n).
7
12, 45, 175, 539, 1573, 2873, 5491, 8303, 15341, 26071, 35557, 56129, 72283, 86903, 117077, 165731, 212341, 249307, 318719, 367993, 420991, 518003, 613121, 768337, 950309, 1050703, 1135163, 1247941, 1342553, 1621663, 2112899, 2351057, 2608891, 2878829, 3352351
OFFSET
1,1
COMMENTS
Subsequence of A014612: a(1)=12=A014612(2), a(2)=45=A014612(10) - Zak Seidov, Apr 26 2016
LINKS
FORMULA
a(n) = A000040(n) * A000040(n) * A000040(n+1).
a(n) = A000040(n) * A006094(n).
a(n) = A001248(n) * A000040(n+1).
MATHEMATICA
a251720[n_Integer] := Prime[#]^2*Prime[# + 1] & /@ Range[n]; a251720[35] (* Michael De Vlieger, Dec 14 2014 *)
#[[1]]^2 #[[2]]&/@Partition[Prime[Range[40]], 2, 1] (* Harvey P. Dale, Mar 12 2015 *)
PROG
(Scheme, three versions)
(define (A251720 n) (* (A000040 n) (A000040 n) (A000040 (+ 1 n))))
(define (A251720 n) (* (A000040 n) (A006094 n)))
(define (A251720 n) (* (A001248 n) (A000040 (+ n 1))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 14 2014
STATUS
approved