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A240052
2nd arithmetic derivative of products of 2 successive prime numbers (A006094).
3
1, 12, 16, 21, 44, 31, 60, 41, 56, 92, 72, 71, 124, 123, 140, 240, 244, 448, 121, 384, 236, 297, 176, 161, 249, 284, 247, 540, 191, 608, 221, 272, 380, 912, 520, 380, 1024, 371, 428, 912, 852, 508, 1472, 433, 696, 297, 293, 705, 860, 493, 716, 1456, 668, 512, 924, 636, 1188, 552, 669, 764, 2112, 1340, 521, 1504, 951, 1836, 672, 1176, 1300, 1107, 1076, 737, 908, 1520, 641, 776, 661, 821, 1647, 1416, 1828
OFFSET
1,2
COMMENTS
The first arithmetic derivative of products of 2 successive prime numbers (A006094) is the sum of 2 successive prime numbers (A001043). A001043 = (A006094)’. The second arithmetic derivative is a(n)=( A001043)’ = (A006094)’’.
LINKS
Wikipedia, p-derivation
FORMULA
a(n) = (A006094(n))''.
EXAMPLE
(2*3)’ = 1*3+2*1 = 5; (5)’ = 1; (2^2)’ = 2*2^1 = 2*2 = 4.
MAPLE
with(numtheory); P:=proc(q) local a, b, c, p, n;
for n from 1 to q do a:=ithprime(n)*ithprime(n+1);
b:=a*add(op(2, p)/op(1, p), p=ifactors(a)[2]);
c:=b*add(op(2, p)/op(1, p), p=ifactors(b)[2]);
print(c); od; end: P(10^3); # Paolo P. Lava, Apr 01 2014
PROG
(Haskell)
a240052 = a068346 . a006094 -- Reinhard Zumkeller, Apr 15 2014
CROSSREFS
Cf. A003415 (1st derivative), A068346(2nd derivative).
Sequence in context: A243538 A183052 A344079 * A363798 A070329 A064695
KEYWORD
nonn
AUTHOR
Freimut Marschner, Mar 31 2014
STATUS
approved