A160130 2 x 2 inner (dot) products taken on corresponding digits in Pi and e.

13, 11, 12, 18, 82, 74, 50, 58, 34, 44, 60, 121, 81, 36, 51, 19, 13, 49, 52, 48, 36, 12, 44, 53, 33, 68, 59, 9, 41, 53, 48, 30, 4, 36, 104, 100, 35, 52, 94, 51, 26, 87, 63, 81, 108, 45, 81, 108, 54, 9, 45, 85, 54, 14, 81, 123, 66, 105, 105, 52, 58, 48, 32

Offset

1,1

Comments

Let pi(n) denote the n-th digit of Pi, and let e(n) denote the n-th digit of e. Define a(n) = pi(n)*e(n) + pi(n+1)*e(n+1).

Links

Table of n, a(n) for n=1..63.

Example

The first two digits of Pi are 3 and 1; the first two digits of e are 2 and 7. Then a(1) = 3*2 + 1*7 = 13.
The second and third digits of Pi are 1 and 4; the corresponding digits in e are 7 and 1; so a(2) = 1*7 + 4*1 = 11.

Mathematica

nn=80; #[[1]]*#[[2]]+#[[3]]*#[[4]]&/@Partition[Riffle[RealDigits[ Pi, 10, nn][[1]], RealDigits[E, 10, nn][[1]]], 4, 2] (* Harvey P. Dale, Jun 13 2011 *)

Crossrefs

Cf. A000796 (Pi), A001113 (e).

Sequence in context: A152298 A158956 A259663 * A340803 A265770 A359868

Adjacent sequences: A160127 A160128 A160129 * A160131 A160132 A160133

Keyword

nonn,base,less

Author

Don Love (moptop35(AT)hotmail.com), May 02 2009

Extensions

Corrected and extended by Harvey P. Dale, Jun 13 2011

Status

approved