cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A240053 3rd Arithmetic derivation of products of 2 successive prime numbers (A006094).

Original entry on oeis.org

0, 16, 32, 10, 48, 1, 92, 1, 92, 96, 156, 1, 128, 44, 188, 608, 248, 1408, 22, 1472, 240, 324, 368, 30, 86, 288, 32, 1188, 1, 1552, 30, 560, 476, 2176, 924, 476, 5120, 60, 432, 2176, 1148, 512, 4480, 1, 1300, 324, 1, 391, 1052, 46, 720, 3232, 672, 2304, 1448, 860, 2484, 1036, 226, 768, 7232, 1628
Offset: 1

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Author

Freimut Marschner, Mar 31 2014

Keywords

Comments

The first arithmetic derivation of products of 2 successive prime numbers (A006094) is the sum of 2 successive prime numbers (A001043). A001043 = (A006094)’. The second arithmetic derivation is (A240052) = (A001043)’ = (A006094)’’. The third arithmetic derivation of products of 2 successive prime numbers (A006094) is a(n) = (A240052)’ = (A001043)’’ = (A006094)’’’.

Examples

			a(12)=(A006094(12))'''=(37*41)'''=(A001043(12))''=(78)''=(71)'=1;
a(14)=(A006094(14))'''=(43*47)'''=(A001043(12))''=(90)''=(123)'=44.
		

Crossrefs

Cf. A003415 (1st derivative), A068346 (2nd derivative), A099306 (3rd derivative).

Programs

  • Maple
    with(numtheory); P:= proc(q) local a,b,c,d,n,p;  a:=ithprime(n)*ithprime(n+1);
    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]);
    d:=c*add(op(2,p)/op(1,p),p=ifactors(c)[2]); print(d);
    od; end: P(10^4); # Paolo P. Lava, Apr 07 2014

Formula

a(n) = (A006094(n))’’’.
a(n) = A099306(A006094(n)).
a(n) = A003415(A240052(n)).

A240054 4th arithmetic derivative of products of 2 successive prime numbers (A006094).

Original entry on oeis.org

0, 32, 80, 7, 112, 0, 96, 0, 96, 272, 220, 0, 448, 48, 192, 1552, 380, 5056, 13, 4480, 608, 756, 752, 31, 45, 912, 80, 2484, 0, 3120, 31, 1312, 572, 7744, 1448, 572, 26624, 92, 1296, 7744, 1340, 2304, 17216, 0, 1920, 756, 0, 40, 1056, 25, 2064, 8112, 2000, 10752, 2180, 1052, 5076, 1212, 115, 3328, 21760, 1820
Offset: 1

Views

Author

Freimut Marschner, Mar 31 2014

Keywords

Comments

Let a'=a1 be the first arithmetic derivative, then a2 is the second and so on. It is interesting to examine the length of successive arithmetic derivatives ending with 1. For example, a(168) = 445 is the 4th arithmetic derivative of prime(168)*prime(169) = 997*1009 = 1005973. The example given here is of length 11; that means that the 11th arithmetic derivative of 1005973 is 1.

Examples

			(997*1009)' = a, a' = a1 = 2006, a2 = 1155, a3 = 886, a4 = 445, a5 = 94, a6 = 49, a7 = 14, a8 = 9, a9 = 6, a10 = 5, a11 = 1.
		

Crossrefs

Programs

  • Maple
    with(numtheory); P:= proc(q) local a,b,c,d,f,n,p;  a:=ithprime(n)*ithprime(n+1);
    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]);
    d:=c*add(op(2,p)/op(1,p),p=ifactors(c)[2]); f:=d*add(op(2,p)/op(1,p),p=ifactors(d)[2]);
    print(d); od; end: P(10^4); # Paolo P. Lava, Apr 07 2014

Formula

a(n) = (A006094(n))''''.
Showing 1-2 of 2 results.